In a Tweet posted earlier in the day, the U.S. Attorney's Office for the District of Massachusetts also said that a press conference would be held Thursday afternoon.
In all, a 30-count indictment was handed down against Tsarnaev. In addition to the three deaths caused by the bombs at the marathon, he was charged with the murder of MIT Police Officer Sean Collier, according to Boston Globe reporter David Abel.
Abel also Tweeted: "Tsarnaev charges include 'bombing of a place of public use' and 'malicious destruction of property resulting in death and conspiracy' ... 'carjacking resulting in serious bodily injury; interference with commerce by threats or violence.' "
The reporter also posted that "17 charges authorize life imprisonment or the death penalty."
Tsarnaev made his initial court appearance from his room in Boston's Beth Israel Hospital a week after the April 15 attacks.
Officials say Tsarnaev and his older brother, Tamerlan Tsarnaev, set off the twin explosions at the Boston Marathon, killing three and injuring more than 180 others.