BOSTON, July 11 (UPI) -- Convicted Boston Marathon bomber Dzhokhar Tsarnaev may face another murder trial for allegedly killing a police officer on the campus of Massachusetts Institute of Technology in the days that followed the attacks.
Middlesex District Attorney Marian T. Ryan said she plans to bring Tsarnaev to trial in the death of Sean Collier, 27, who was shot and killed on April 18, 2013. Prosecutors say Collier was killed by Tsarnaev and his brother, Tamerlan, during the manhunt for the bombers.
Tamerlan Tsarnaev was killed during a confrontation with police and Dzhokhar was captured hours later.
Last month, following his conviction, Tsarnaev was sentenced to death for helping carry out the marathon attack. He was then transported to a maximum security prison in Colorado, but it remains unknown exactly where Tsarnaev will be incarcerated until his execution by lethal injection.
It also was unclear when the new trial might be held, but Ryan said her office had only recently began the process of asking the federal government to return Tsarnaev to Massachusetts, the Boston Globe reported.
"When you come into Middlesex County and execute a police officer in the performance of his duties and assault other officers attempting to effect his capture, it is appropriate you should come back to Middlesex County to stand trial for that offense," Ryan said.
The effort to try Tsarnaev for Collier's death -- which will involve the use of taxpayer dollars -- might be met with some resistance, as the 21-year-old is already on death row.
Ryan, however, mentioned that Tsarnaev's federal case won't be finalized until the appeals process is exhausted.
The Globe's report cited some experts as saying they couldn't think of any previous case in which a convict on federal death row was subsequently tried at the state level.