BOSTON - The two brothers suspected of bombing the Boston Marathon appear to have been motivated by their religious faith but do not seem connected to any Muslim terrorist groups, U.S. officials said Monday after interrogating the severely wounded younger man. He was charged with federal crimes that could bring the death penalty.
Dzhokhar Tsarnaev, 19, was charged in his hospital room with using a weapon of mass destruction to kill. He was accused of joining with his older brother, Tamerlan - now dead - in setting off the pressure-cooker bombs that killed three people and wounded more than 200 a week ago.
The brothers, ethnic Chechens from Russia who had been living in the U.S. for about a decade, practiced Islam.
Newton Fire Department Lt. Mike Murphy carries an American flag down the middle of Boylston Street after observing a moment of silence in honor of the victims of the bombing at the Boston Marathon near the race finish line Monday.
Dzhokhar Tsarnaev communicated with his interrogators in writing, a less-than-ideal format that precluded the type of detailed back-and-forth crucial to establishing the facts, said one of two officials who recounted the questioning. They spoke on condition of anonymity because they were not authorized to publicly discuss the investigation.
The two officials said the preliminary evidence from an interrogation suggests the Tsarnaev brothers were driven by religion but had no ties to Islamic terror organizations.
At the same time, they cautioned that they were still trying to verify what they were told by Dzhokhar Tsarnaev and were looking at such things as his communications and his associations with others.
The criminal complaint containing the charges against Dzhokhar Tsarnaev shed no light on the motive.
But it gave a detailed sequence of events and cited surveillance-camera images of him dropping off a knapsack with one of the bombs and using a cellphone, perhaps to coordinate or detonate the blasts.
The Massachusetts college student was listed in serious but stable condition at Beth Israel Deaconess Medical Center with a gunshot wound to the throat and other injuries. His 26-year-old brother died last week in a gunbattle with police.
"Although our investigation is ongoing, today's charges bring a successful end to a tragic week for the city of Boston and for our country," Attorney General Eric Holder said.
The charges carry the death penalty.
"He has what's coming to him," a wounded Kaitlynn Cates said from her hospital room. She was at the finish line when the first blast knocked her off her feet, and she suffered an injury to her lower leg.
In outlining the evidence against him in court papers, the FBI said Tsarnaev was seen on surveillance cameras putting a knapsack down on the ground near the site of the second blast and then manipulating a cellphone and lifting it to his ear.
Seconds later, the first explosion went off about a block down the street and spread fear and confusion through the crowd. But Tsarnaev - unlike nearly everyone around him - looked calm and quickly walked away, the FBI said.
Just 10 seconds or so later, the second blast occurred where he had left the knapsack, the FBI said.
The FBI did not make it clear whether authorities believe he used his cellphone to detonate one or both of the bombs or whether he was talking to someone.
The court papers also said that during the night of crime Thursday and Friday that led to the older brother's death and the younger's capture, one of the brothers told a carjacking victim: "Did you hear about the Boston explosion? I did that."
In addition to the federal charges, the younger Tsarnaev brother is also likely to face state charges in connection with the shooting death of an MIT police officer.
In its criminal complaint, the FBI said it searched Tsarnaev's dorm room at the University of Massachusetts-Dartmouth on Sunday and found BBs as well as a white hat and dark jacket that look like those worn by one of one of the suspected bombers in the surveillance photos released after the attack.