Federal authorities said the charge sheet against Dzhokar could be filed early next week by the US Attorney General.
Investigating agencies, including the FBI, the Boston Police, are busy preparing the charge sheet against 19-year-old Dzhokar, as a senior police official today said they have enough evidence to nail down the suspect.
Tamerlan Tsarnaev, 26, was pronounced dead on Friday after suffering shrapnel and bullet wounds in a gunfight with police, while his brother Dzhokhar was later arrested in connection with the bombings that killed three people.
Those involved in preparing the charge sheet said Dzhokar, who was arrested on Friday night, would be charged with terrorism and state murder charges.
The Boston Mayor had told reporters earlier that he could be charged as early as Sunday, but that did not happen.
Boston City Police chief Ed Davis said the suspect is in no condition to be interrogated at this point in time.
"He's progressing, though, and we're monitoring the situation carefully," he said. "Despite a serious throat wound preventing him from speaking, the surviving Boston Marathon bombing suspect is beginning to respond to questions from investigators," NBC news said quoting unnamed federal officials.
"He was responding to questions mostly in writing because of the throat wound, according to the officials, who spoke on condition of anonymity. The suspect remains in serious condition," the news channel said. "Investigators are asking about other cell members and other unexploded bombs," ABC news reported.
"Officials did not reveal further details on what they are asking or what his responses are," CBS news said. However, there was no official word on the health status of Dzhokar.
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