This handout image, District of Massachusetts, presented to jurors on March 23, 2015 in Boston, Massachusetts, shows Dzhokhar Tsarnaev Boston Marathon bomber. (US Department of Justice/US Attorney's Office, AFP)
Convicted Boston marathon bomber Dzhokhar Tsarnaev could stand trial on state charges for the murder of a police officer despite being on death row at a federal prison, a report said Saturday.
Tsarnaev was convicted in federal court in Boston in April and formally sentenced to death last month over the 2013 bomb attacks that left three dead and 264 injured in one of the bloodiest assaults in America since the September 11, 2001 attacks.
The 21-year-old Tsarnaev was found guilty on all counts related to the bombings, the subsequent murder of Massachusetts Institute of Technology (MIT) police officer Sean Collier, a carjacking and a shootout while on the run.
Now Middlesex County District Attorney Marian Ryan reportedly plans to bring Tsarnaev back to Massachusetts to face state charges in connection with the MIT officer's murder.
Ryan told The Boston Globe it was "appropriate" to go after Tsarnaev again because the federal convictions are not final pending appeal.
"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," the newspaper quoted Ryan saying in a statement.
Tsarnaev - a Muslim immigrant who took US citizenship - also faces several other state charges, including carjacking and kidnapping, the report added.
The Boston Globe, citing experts, said they were unable to think of another case in which someone on federal death row was tried again on additional state charges.
Tsarnaev's older brother Tamerlan, 26, was shot dead by police, leaving Dzhokhar to stand trial alone after he was captured.