Despite media reports, police deny they've arrested a suspect over the deadly Boston Marathon bombings.
AUTHORITIES investigating the Boston Marathon bombings are reportedly looking to talk to a man wearing a white baseball cap as conflicting reports emerge suggesting he may be a suspect.
Several news agencies are reporting having seen the pictures, which have not yet been authorised for release. They purport to clearly show two men, one carrying a backpack similar to the one used in the blast and the other carrying several other bags.
The FBI has emphatically denied it has made an arrest. Speculation continues as to whether or not they are questioning any suspects.
Meanwhile 100 of the 170 wounded have been released from hospital while mourners have remembered the three victims - Chinese mathematics student Lingzi Lu, eight-year-old Martin Richard and 29-year-old Krystle Campbell.
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8pm: For more updates on the Boston Marathon bomber manhunt from here, click on our next wrap
6.10pm: President Barack Obama will attend a service, to be held at 11am Thursday at the Cathedral of the Holy Cross in the city's South End, where he will try to comfort a community in deep mourning, The Boston Globe reports.
Obama will deliver a message "of resolve" to Boston, White House Press Secretary Jay Carney said. "It will be [a message] of the commonality that we all feel as Americans with the people of Boston and those who were visiting Boston for the Marathon and who both endured this horrific event and then demonstrated their bravery in its immediate aftermath." Michelle Obama is scheduled to accompany him.
The Obamas are scheduled to be in Boston several hours, which suggests they may also be meeting with bombing victims.
Boston firefighters, right, talk with FBI agents and a crime scene photographer at the scene of Monday's Boston Marathon explosions, which killed at least three and injured more than 140, in Boston, Tuesday, April 16, 2013. (AP Photo/Charles Krupa)
5.04pm: Adelaide mother Anna Liptak and her running partner Chantel Peacock have arrived home in Adelaide today after their Boston bombing ordeal.
Exhausted after a 28-hour flight, Liptak, 39, said she was relieved to be home with by husband Nick Shinnick, their sons Zach, 9, and Lachy, 7, and her parents George and Margaret.
"It's really nice to be home with the family," the sister of former Adelaide Crows player Matthew Liptak said.
4.11pm: More details about the surveillance video purportedly showing a man near the site of the attack has emerged. Sources say investigators are trying to identify a person standing in the crowd near the scene of the second bombing just before the device exploded, reported CBS News correspondent Bob Orr. A surveillance camera at a nearby Lord and Taylor department store captured images of the man who was carrying a backpack and talking on a mobile phone.
The man was wearing a black jacket, a grey hooded sweatshirt and a white or off-white baseball cap backwards. Investigators say he put the backpack on the ground. Then, he fled after the first bomb went off. Seconds later, the second bomb exploded near where he was.
Investigators now are going through mobile phone logs to determine who made calls from that location near the time of the explosions. Sources say the FBI is working with a list of names of mobile phone owners and attempting to match one of those to the unknown man.
Sources say forensic experts tape will attempt to use facial recognition software and compare the images from the surveillance camera to photo IDs connected to known mobile phone users.
3.50pm: In typical Boston fashion, the Bruins held an emotional pre-game ceremony to honor the victims of the marathon bombings. Once the Bruins started their ice hockey game, the 17,565 fans at the game gave the city's hockey team a standing ovation.
Bruins coach Claude Julien said: "It was pretty emotional. In a way, it makes you feel proud of the city and of our fans and the solidarity that was shown throughout this whole thing. "I'm proud of this city for how it responded tonight."
2.29pm: Officials have prevented Perth runners from holding a memorial run in honour of the victims of the Boston Marathon bombings.
2.25pm: Up to 70 are feared dead after an explosion occurred at a fertiliser plant near Waco, Texas. The explosion has forced the town of West to evacuate after it ripped through buildings, destroying peoples' homes. Adults and children were trapped. Latest here.
1.40pm: US investigators have found images of a suspect who may have planted the bombs that killed three people and maimed scores more at the Boston Marathon, AFP reports.
No arrest has been made. But images from a surveillance camera and still pictures could mark a breakthrough ahead of a visit to the city by US President Barack Obama and his wife Michelle in what was being billed as a mission of "healing." Conflicting reports of an arrest brought a stern rebuke from the Federal Bureau of Investigation.
Lizzie Lee, 56, holds a candle and a flower at Boston Commons during a vigil for the victims of the Boston Marathon explosions. Picture: AP Photo/Julio Cortez
But a law enforcement official told AFP that "there is an image of a person, of a potential suspect."Investigators were working "to locate and identify that individual," the official added.
The Boston Globe said the images may have captured the suspect planting one of the two bombs. Separate media reports indicated there were pictures of the suspect running away while other people slumped to the ground during the blast.
1.25pm: Man's best friend has been helping victims of the Boston bombings, with comfort dogs visiting the sick and wounded in hospital, NBC reports.
The Lutheran Church Charities are taking their K-9 Comfort Dogs around hospitals in Boston to help the injured and also those who witnessed the tragedy, many of who m are struggling with grief and anxiety.
"We have people simply walking by on the sidewalk who see the dogs - and with the memory of Monday, they break into tears," Reverend Ingo Dutzmann said. "It's the dog that allows them to express their emotions in that way, and if you're hurting, you've got to let it go. With a dog, people are not afraid to do that."
12.50pm: As Bostonians struggle with their grief in the wake of the marathon bombings, pictures of the tragedy have set off a debate in some US media outlets about publishing images like this one, The New York Times reports:
Medical workers aid the injured people following the bombings at the Boston Marathon. Picture: AP/The Boston Globe, David L Ryan Source: AP
Given the nature of carnage, some are asking if images of bloody and badly wounded runners should be printed at all either online or on the front pages of major newspapers.
Others argue that while such images may shock readers they also honestly represent the true nature of such an event.
A heavily armed United States Marshall stands guard outside the Moakley Federal Court House in Boston after the building was evacuated due to a bomb threat. Picture: AP Photo/Michael Dwyer
12.35pm: Modern Family actress Sofia Vergara is among those counting her lucky stars as her son Manolo, who goes to college in Boston, was not in town when the tragedy struck.
"Thank God he was not there or I would have become crazy," she told The Associated Press. "I know for a lot of mothers it was a difficult time because the phone lines were so busy. I'm sure that for all the hours and minutes - whatever that lasted -I'm sure it was horrible."
12.10pm: Meanwhile ABBA star Björn Ulvaeus has apologised for an ill-timed joke he made about the bombings during an appearance on BBC One Breakfast in London.
When asked how he keeps in shape, the 67 year-old replied: "Well, I don't know, running is good - unless you're in the Boston Marathon," he said, before quickly adding "Which is terrible". He later released a statement saying he was sorry for what he said and felt bad about what he called an "unbelievably stupid slip of the tongue".
11.59am: More bad news coming from Texas, with The Waco Tribune reporting several firefighters are among those critically injured in the blast at the fertilizer plant.
A radio dispatcher called for several ambulances to attend saying "we do have a lot of injured here".
11.20am: While Boston is still reeling from the recent tragedy of the marathon bombings, news is emerging of a fertilizer plant exploding in Waco, Texas. There are reports that residents at a near-by old age home and children at a local school may be trapped as a result of blast.
The explosion comes just days before the 20th anniversary of the end of the FBI siege of David Koresh's compound in Waco.
10.55am: The bombs that made Boston look like a combat zone have also brought battlefield medicine to their civilian victims, AP reports.
Boston Bruins hockey starters, including defenseman Dennis Seidenberg (44), stand next to a ribbon projected onto the ice at TD Garden to remember those who died in the Boston Marathon bombings. Picture: AP Photo/Elise Amendola
A decade of wars in Iraq and Afghanistan has sharpened skills and scalpels, leading to dramatic advances that are now being used to treat the 13 amputees and nearly a dozen other patients still fighting to keep damaged limbs after the attack.
"The only field or occupation that benefits from war is medicine," said Dr. David Cifu, rehabilitation medicine chief at the Veterans Health Administration.
Nearly 2,000 U.S. troops have lost a leg, arm, foot or hand in Iraq or Afghanistan, and their sacrifices have led to advances in the immediate and long-term care of survivors, as well as in the quality of prosthetics that are now so good that surgeons often choose them over trying to save a badly mangled leg.
10.40am: Amid the focus on the ongoing Boston bombings investigation, police arrested a man with a loaded weapon outside the Capitol building in Washington, CNN reports.
The man, who was carrying a loaded handgun, was protesting against legislation which would have expanded the background checks on those who wish to buy guns. The bill was defeated and police arrested the man for carrying a gun without a license.
10.30am: More details have emerged about the arrest of the Mississippi man believed to be responsible for sending the ricin-laced letters to President Barack Obama and Senator Roger Wicker.
The arrest took place in the town of Tupelo, the hometown of Senator Wicker.
Authorities are still conducting tests on the letters which had raised concern at a time when many people were jittery after the Boston bombings.
10.10am: NHL team the Boston Bruins tweeted a poignant photograph of the moment when the national anthem was played before their game against the Buffalo Sabres.
Richard Maldonado lights a candle at a makeshift memorial on Boylston Street near the finish line of the Boston Marathon. Picture: AP Photo/Matt Rourke
NHL team the Boston Bruins tweeted this photo of the projected image of the ribbons many are wearing to remember those who lost their lives in the marathon with this caption : Blue and yellow ribbons projected on the ice during national anthem. Picture: Twitter/ Boston Bruins Source: Twitter
As the anthem played, a light image of the blue and yellow ribbons many have been wearing in honour of the victims of the Boston Marathon bombings, was projected onto the ice. The team also observed a moment of silence before the match began.
10.00am: While the investigation into the Boston tragedy continues, the mounting medical bill for those wounded by the twin blasts could top $9 million, NBC news reports.
That amount only concerns the 70 who remain in hospital, not the 100 who have already been released. Experts say the severe nature of their wounds will mean many face a long recovery.
Some will require rehabilitation to help them learn to re-walk and face life without the limbs they lost in the blast and experts say post traumatic stress disorder could also be an issue for survivors.
9.35am: The Boston Police Department has announced the FBI has cancelled its briefing scheduled for 8pm local time (10am AEST).
9.30am: The Boston Globe has added its voice to reports that police have pictures of a suspect. They report the suspect has been identified on a video carrying a black bag near the scene of the second bombing at the Boston Marathon.
An official told the Boston Globe newspaper that surveillance video for a nearby Lord & Taylor department store showed clear images of the scene. No further details about the suspect were provided.
9.25am: Several US media sources are reporting an arrest has been made in relation to possibly poisoned letters being sent to leading politicians.
NBC and CBS report a suspect has been arrested for sending letters to President Obama and Senator Wicker. NBC name him as Kenneth Curtis of Tupelo, Mississippi.
9.11am: Fox News' Rick Leventhal says he has seen photographs being circulated by authorities that show two men, one with a backpack and the other carrying bags. He says he is not permitted to publish the picture. He says the pictures are "pretty clear with multiple angles and you can definitely see their faces."
8.24am: Investigators have an image from surveillance video of a man dropping off a bag containing one of the bombs and may be on the verge of arresting a suspect, a politician said.
City Council President Stephen Murphy said he didn't know if investigators have identified the man, who was seen on surveillance footage from a nearby department store. Murphy said police involved in the probe say investigators have matched information from the footage with witness descriptions of someone leaving the scene.
"They may be on the verge of arresting someone and that's good," Murphy said.
8.16am: A US marine Afghan veteran who comforted a frightened wounded college student said he saw the terror in her eyes and knew he had to talk to her.
Sgt. Tyler Dodd staid with Northeastern University student Victoria McGrath who credits him with keeping her calm in a medical tent by showing her a shrapnel wound on his leg.
"You're going to have a scar, but you're going to be OK. It'll be like my scar," he reportedly told her.
8.02am: While the world waits with baited breath and 24 hour cable news stations fill air time with theories about who may responsible for the double bombing in Boston, Massachusetts Governor Deval Patrick is urging patience.
Speaking at a news conference, Governor Patrick asked that both the media and the public be patient and let investigators get on with the task of sifting through evidence and building a case against those responsible.
7.30am: A suspected component of a bomb used in the deadly Boston marathon attack was found by accident on the roof of a city hotel, the owner told AFP on Wednesday.
The pressure cooker lid was found atop the Charlesmark Hotel, close to the marathon finish line where the bombs were placed, said owner Mark Hagopian.
Investigators have said they believe the bombs, which killed three and injured around 180, were packed in pressure cookers and the lid could provide valuable evidence in the hunt for the attackers.
"The guest who found it should not have been on the roof," Hagopian said. "Normally the door is locked."
The man, from Portland, Oregon, had already been told to leave the rooftop, six floors above street level, after police spotted him there on the morning of the marathon, Hagopian added.
"Police told us to clear it," he said.
6.45am: The latest news from Boston is anything but clear, with a possible suspect being identified but reports varying widely as to who the suspect may be, what he may or may not have been wearing and how police have identified him.
CNN are reporting the suspect was identified as wearing a white baseball cap backwards while other media outlets have described him as a dark-skinned man.
6.30am: Students in Boston have remembered their classmate Lu Lingzi from China who was also killed in the bombings. She had been studying mathematics and was due to graduate in 2015.
Less than 24 hours before she died, Lu Lingzi sent an exuberant email to a professor after learning she had passed part of a major final exam.
"I am so happy to get this result!" she wrote. "Thank you very much."
Hundreds of students attended a memorial service for Ms Lu at Boston University on Tuesday night. Thousands of tributes were posted online on Chinese websites.
This undated photo provided by Meixu Lu shows Lingzi Lu in Boston. Boston University confirmed Wednesday, April 17, 2013, that Lingzi Lu, who was studying mathematics and statistics at the school and was due to receive her graduate degree in 2015, was among the people killed in the explosions at the finish line of the Boston Marathon Monday, April 15, 2013, in Boston. (AP Photo/Meixu Lu) Source: AP
Lu was a vivacious chatterbox who had lots of friends on campus, said Tasso Kaper, chair of the mathematics and statistics department, whose face lit up talking about his former student.
"The word bubbly - that's kind of a corny word - but that describes her very well," Kaper said.
Lingzi's closest friends in Boston did not learn that she had been killed until Tuesday evening, when they were informed by faculty members. Fellow graduate students are struggling to process her death.
"Many of them are still in shock and disbelief," Kaper said.
Overnight there was a small, private gathering of friends and faculty at the math department to "begin the long grieving process," Kaper said.
6.15am: With tight security in place in Boston and other cities around the US including Washington, a letter sent to President Barack Obama has tested positive for the poison Ricin.
The FBI said the letter had the same postmark- Memphis, Tennessee- as the letter sent to Senator Roger Wicker which tested positive for the same substance. Both letters were intercepted before they reached either the White House or the US Senate.
6.02am: Runners from the Newtown Strong Fund team, who competed in the marathon in memory of those who died in the Sandy Hook shooting, the Boston tragedy has been a blow to efforts to get back to normal life.
Dr Laura Nowacki said running was her escape and after the December shooting it had given her a sense of freedom which has been shattered by the bombings.
FROM OVERNIGHT: A law enforcement official briefed on the investigation told The Associated Press earlier in the day that a suspect was in custody. The FBI and the US attorney's office in Boston said that no arrests had been made.
The official who spoke to the AP did so on condition of anonymity and stood by the information even after it was disputed. The official, who was not authorised to divulge details of the investigation, had said the suspect was expected in federal court in Boston.
CNN reported Boston authorities identified the suspect from CCTV footage at department store Lord & Taylor, near the site of the second blast. TV footage from a local Boston station was also used to help make the ID, sources said. Authorities had earlier appealed to the public for photos and video of the event.
Authorities said they may have an image of a suspect carrying, and maybe even dropping, a black bag at the second bombing scene, the Boston Globe reported. Investigators said they were "very close", an official briefed on the Boston Marathon bombing told the Globe.
"The camera from Lord & Taylor is the best source of video so far, " Boston Mayor Thomas M. Menino's spokeswoman Dot Joyce was quoted in the Globe.
