Federal officials denied a suspect was under arrest Wednesday in the Boston Marathon bombings.
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 U.S. 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 authorized to divulge details of the investigation, had said the suspect was expected in federal court in Boston.
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.
"Contrary to widespread reporting, there have been no arrests made in connection with the Boston Marathon attack," the FBI said in a statement. "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."
The Boston courthouse was evacuated by authorities in the afternoon because of what they called an 'unrelated' bomb threat that later proved to be unfounded.
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. Police also gathered surveillance video from businesses around the finish line.
The bombs were made from ordinary kitchen pressure cookers packed with explosives, nails and ball bearings to inflict maximum carnage, investigators and others close to the case said. But the FBI said nobody had claimed responsibility.
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.