UNKNOWN - APRIL 19: In this image released by the Federal Bureau of Investigation (FBI) on April 19, 2013, Dzhokhar Tsarnaev, 19-years-old, a suspect in the Boston Marathon bombing is seen. After a car chase and shoot out with police one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two are suspects in the bombings at t
USA TODAY - Dzhokhar Tsarnaev, the surviving suspect in the Boston Marathon bombings, is awake in a Boston hospital and responding in writing to questions, a law enforcement official said Sunday.
Investigators who have been waiting to interrogate Tsarnaev are looking into the possibility that his neck wound was self inflicted, a federal law enforcement official said.
The official, who has been briefed on the matter but is not authorized to comment publicly, said that suspicions of a suicide attempt before he was captured center on the small appearance of the entry wound and larger exit wound area
A law enforcement official confirmed that the suspect was awake Sunday evening. Earlier, Boston Police Commissioner Ed Davis told reportersthat Tsarnaev was still "not in any condition to be interrogated.'' He said the suspect's condition has only stabilized in "the last few hours.''
Though the suspect's condition was listed as serious, Davis said "serious and critical are interchangeable.''
Separately, the official said it will likely take "some time'' before agents are able to review information held by Russian authorities that prompted the Russian government to ask the FBI in 2011 to review the activities of Tamerlan Tsarnaev, the older brother who died in a gunfight with police in Watertown.
The U.S. attorney's office, meanwhile, said no charges would be filed Sunday.
Davis said on CBS' Face the Nation that police believe Tsarnaev and his brother, Tamerlan Tsarnaev, 26, "were going to attack other individuals."
Dzhokhar Tsarnaev, who was captured Friday after a dramatic manhunt that paralyzed Boston and its suburbs, is under heavy guard in a Boston hospital.
The brothers' uncle, Ruslan Tsarni, told the Associated Press that Dzhokhar Tsarnaev was "used" by his older brother to carry out the bombing. "He's not been understanding anything," Tsarni said. "He's a 19-year-old boy."
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The Tsarnaev family are ethnic Chechens who came to the United States from Kyrgyzstan and Dagestan.
Tsarni also told the AP that his relationship with his nephews deteriorated several years ago when Tamerlan Tsarnaev "started carrying all this nonsense associated with religion, with Islamic religion" and began using words such as "jihad" without really understanding their meaning.
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