WASHINGTON - Federal officials say a suspect in the Boston Marathon bombing is not in custody, according to The Associated Press.
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A law enforcement official briefed on the investigation told AP on Wednesday morning a suspect was in custody. However, the FBI and the U.S. attorney's office in Boston are disputing that.
The official who spoke to AP 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.
The Boston Police Department said no arrest has been made in connection with the Boston Marathon bombing despite earlier media reports.
At about 11:30 a.m. Pacific time, Boston police tweeted, "Despite reports to the contrary there has not been an arrest in the Marathon attack."
At 11:45 a.m. Pacific time, a Department of Justice official told CNN that no arrest was made.
In a statement posted on ABCNews.com, the FBI said:
"Contrary to widespread reporting, there have been no arrests 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."
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.
A person close to the investigation had previously told AP the bombs consisted of explosives put in 1.6-gallon pressure cookers, one with shards of metal and ball bearings, the other with nails.
Investigators in white jumpsuits had fanned out across the streets, rooftops and awnings around the blast site in search of clues on Wednesday. They combed through debris amid the toppled orange sports drink dispensers, trash cans and sleeves of plastic cups strewn across the street at the marathon's finish line.
President Barack Obama branded the attack an act of terrorism. Obama plans to attend an interfaith service Thursday in the victims' honor in Boston.
Scores of victims of the Boston bombing remained in hospitals, many with grievous injuries. Doctors who treated the wounded corroborated reports that the bombs were packed with shrapnel intended to cause mayhem. In addition to the 5-year-old child, a 9-year-old girl and 10-year-old boy were among 17 victims listed in critical condition.
The trauma surgery chief at Boston Medical Center says most of the injuries his hospital treated after the marathon bombings were to the legs.
"We have a lot of lower extremity injuries, so I think the damage was low to the ground and wasn't up," Dr. Peter Burke said. "The patients who do have head injuries were blown into things or were hit by fragments that went up."
Dozens of patients have been released from hospitals around the Boston area.
At Massachusetts General Hospital, all four amputations performed there were above the knee, with no hope of saving more of the legs, said Dr. George Velmahos, chief of trauma surgery.
"It wasn't a hard decision to make," he said Tuesday. "We just completed the ugly job that the bomb did."
An intelligence bulletin issued to law enforcement includes a picture of a mangled pressure cooker and a torn black bag that the FBI said were part of a bomb that exploded during the marathon.
The bombs exploded 10 or more seconds apart, tearing off victims' limbs and spattering streets with blood. The blasts near the finish line instantly turned the festive race into a hellish scene of confusion, horror and heroics.
The blasts killed 8-year-old Martin Richard, of Boston, and 29-year-old Krystle Campbell, of Medford. The Shenyang Evening News, a state-run Chinese newspaper, identified the third victim as Lu Lingzi. She was a graduate student at Boston University.