BOSTON -- Sixteen hours after investigators began interrogating him, the surviving suspect in the Boston Marathon bombings went silent: He'd just been read his constitutional rights.
Dzhokhar Tsarnaev immediately stopped talking after a magistrate judge and a representative from the U.S. Attorney's office entered his hospital room and gave him his Miranda warning, according to a U.S. law enforcement source and four officials of both political parties briefed on the interrogation. They insisted on anonymity because the briefing was private.
Before being advised of his rights, the 19-year-old suspect told authorities that his older brother, Tamerlan Tsarnaev, 26, only recently had recruited him to be part of the attack that detonated pressure-cooker bombs at the marathon finish line, two U.S. officials said.
The CIA, however, had named Tamerlan to a terrorist database 18 months ago, said officials close to the investigation who spoke to The Associated Press on condition of anonymity because they were not authorized to discuss the case with reporters.
The new disclosure that Tamerlan Tsarnaev was included within a huge, classified database of known and suspected terrorists before the attacks was expected to drive congressional inquiries in coming weeks about whether the Obama administration adequately investigated tips from Russia that Tsarnaev had posed a security threat.
Shortly after the bombings, U.S. officials said the intelligence community had no information about threats to the marathon before the April 15 explosions that killed three people and injured more than 260.