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5:55PM EDT: (AP) A politician says investigators poring over photos and videos from the Boston Marathon bombing have an image of a man dropping off a bag containing one of the bombs.

City Council President Stephen Murphy said Wednesday investigators saw the image on surveillance footage they got from a nearby department store. He says he doesn’t know if investigators have identified the man.

Murphy says police officers involved in the probe say investigators have matched information from the surveillance footage with witness descriptions of someone leaving the scene.

Murphy says officers are chasing leads that could take them to the man. He says developing that information within the first 48 hours of the probe is a major breakthrough.

4:44PM EST: The bomb squad has officially called off the bomb threat. The  Daily Media briefing  that was originally scheduled at 5:00 PM EST   has been postponed in light of events at the Moakley Courthouse.

4:01PM EST: The FBI has just released a statement regarding today’s developments:

“Contrary to widespread reporting, no arrest has been made in connection with the Boston Marathon attack. Over the past day and a half, there have been a number of press reports based on information from unofficial sources that has been inaccurate. Since these stories often have unintended consequences, we ask the media, particularly at this early stage of the investigation, to exercise caution and attempt to verify information through appropriate official channels before reporting”

3:51PM EST: Conflicting reports are surfacing whether the bomb threat at the Federal courthouse has been officially cleared. YWN will keep following this story with the latest developments.

3:26PM EST Marshals are moving people away from the Boston Federal Court parking lot. The Boston bomb squad has arrived in  response to a bomb threat that was called in.

2:56PM EST: (AP) Federal officials are denying that a suspect is in custody in the Boston Marathon bombings.

A law enforcement official briefed on the investigation told The Associated Press on Wednesday a suspect was in custody.

But the FBI and the U.S. attorney’s office in Boston dispute that.

The official who spoke to The Associated Press did so on condition of anonymity and stood by the information even after it was disputed.

The official was not authorized to divulge details of the investigation. The official had said the suspect was expected in federal court in Boston.

Reporters and police have converged at the courthouse.

2:54PM EDT: (Reuters) The U.S. Attorney’s Office in Boston said that no suspect has been arrested in connection with the probe of the Boston Marathon bombing, according to spokeswoman Brandy Donini-Melanson.

2:51PM EDT: (Reuters) Investigators believe they have identified a suspect in the Boston Marathon bombing from security video and an official statement was expected later in the day, a U.S. law enforcement source said on Wednesday.

However, no arrest had been made, three separate U.S. government and law enforcement sources told Reuters.

Police may make an appeal to the public for more information at a news conference scheduled for later on Wednesday, a U.S. government source said.

Earlier, CNN reported that a suspect was in custody, citing law enforcement sources. But then the network cited three sources who said no one was under arrest after all.

The identification of a possible suspect marked the most significant publicly disclosed break since Monday’s blast at the marathon finish line killed three people and injured 176 others.

2:38PM EDT: Boston police tweeted following: “Despite reports to the contrary there has not been an arrest in the Marathon attack.”

2:35PM EDT: (Reuters) There have been no arrests made yet in the bombings at the Boston Marathon that left three people dead and scores injured, U.S. government and law enforcement sources said on Wednesday.

One of the sources said there was no one in custody either.

2:23PM EDT: (AP) A suspect in the Boston Marathon bombings was taken into custody Wednesday in a breakthrough that came less than 48 hours after the deadly attack, a law enforcement official briefed on the investigation said Wednesday.

The official spoke shortly after several media outlets reported that a suspect had been identified from surveillance video taken at a Lord & Taylor store between the sites of the two bomb blasts, which killed three people and wounded more than 170.

The official was not authorized to divulge details of the investigation and spoke to The Associated Press on condition of anonymity. The suspect was expected at a Boston courthouse under heavy security, the official said.

A news briefing was scheduled later Wednesday.

2:10PM EDT: (AP) A law enforcement official briefed on the investigation says a suspect has been taken into custody in the Boston Marathon bombings.

The official spoke to The Associated Press on condition of anonymity Wednesday. The official was not authorized to divulge details of the investigation.

The official says the suspect is expected in federal court in Boston.

Law enforcement agencies had earlier pleaded for the public to come forward with photos, videos or any information that might help them solve the twin bombings that killed three people and wounded more than 170 on Monday.

Investigators circulated information about the bombs, which involved kitchen pressure cookers packed with explosives, nails and other lethal shrapnel. But the FBI said nobody had claimed responsibility.

2:08PM EDT: (Reuters) Authorities have arrested a suspect in the Boston Marathon bombings based on security video that showed a man depositing a bag at the scene before the blasts, CNN reported on Wednesday, citing U.S. and Boston law enforcement sources.

A U.S. law enforcement source told Reuters that a suspect had been identified and that a formal announcement would be made later in the day.

The developments are the biggest publicly-disclosed breaks since Monday’s blast at the marathon finish line killed three people and injured 176 others. Investigators were searching through thousands of pieces of evidence from cell phone pictures to shrapnel shards pulled from victims’ legs.

Based on shards of metal, fabric, wires and a battery recovered at the scene, the focus turned to whoever may have made bombs in pressure cooker pots and taken them in heavy black nylon bags to the finish line of the world-famous race watched by crowds of spectators.

1:55PM EDT: Authorities have arrested a suspect in the Boston Marathon bombings based on security video that showed a man depositing a bag at the bomb scene before the blasts, CNN reported on Wednesday, citing U.S. and Boston law enforcement sources.

1:50PM EDT: BOSTON BOMB SUSPECT IN CUSTODY, CNN REPORTS, CITING UNNAMED U.S. LAW ENFORCEMENT SOURCE.

1:40PM EDT: A source tells NewsCenter 5’s Janet Wu that Boston authorities believe they have identified a suspect in bombings. An arrest is imminent or may have already taken place.

UPDATE 1:00PM EDT: Investigators believe they have identified a suspect in the Boston Marathon bombings, a source who has been briefed on the investigation told CNN’s John King.

The source said what officials believe is a breakthrough came from analysis of video from a department store near the site of the second explosion. Video from a Boston television station also contributed to the progress, this source said.

From that analysis, the source said, authorities believe that they have identified a suspect.

The source declined to be more specific but called it a significant development.

12:58PM EDT: (Reuters) Investigators of the Boston Marathon bombings believe they have identified a suspect from security video taken before Monday’s blasts killed three people and injured 176 others, a U.S. law enforcement source said on Wednesday.

The source said an official announcement was expected later on Wednesday in what is the first major publicly disclosed break in the investigation.

Investigators of the bombings searched thousands of pieces of evidence from cell phone pictures to shrapnel shards pulled from victims’ legs.

Based on shards of metal, fabric, wires and a battery recovered at the scene, the focus turned to whoever may have made bombs in pressure cooker pots and taken them in heavy black nylon bags to the finish line of the world-famous race watched by crowds of spectators.

A stretch of Boston’s Boylston Street almost a mile long and blocks around it remained closed as investigators searched for clues in the worst attack on U.S. soil since the hijacked plane strikes of Sept. 11, 2001.

Cities across the United States were on edge after Monday’s blasts in Boston. Adding to the nervousness was the announcement that mail containing a suspicious substance addressed to a lawmaker and to President Barack Obama. The FBI said, however, that agents had found no link the attack in Boston.

(YWN World Headquarters – NYC)