A man who spent 21 years behind bars for a killing he insisted he did not commit will not face a second trial, prosecutors announced Monday.

Angel Echavarria, 48, was released from prison last month after an Essex County Superior Court judge vacated a life sentence and granted a new trial in the 1994 shooting death of Daniel Rodriguez in Lynn.

On Monday, Essex District Attorney Jonathan Blodgett dropped a murder charge and said he will not re-try Echavarria.

"Given the lapse in time, our inability to locate witnesses and the lack of forensic evidence not affected by time, it is not feasible to re-try the case at this time," Blodgett said in a statement.

The new trial had been granted after a decade-long investigation by the Schuster Institute for Investigative Journalism at Brandeis University. Judge David Lowy granted the motion based in part on ineffective work by Echavarria's trial lawyer.

The state's case against Echavarria was based largely on eyewitness testimony from the victim's brother, who did not speak English and was a habitual marijuana user.

The institute had no immediate comment on prosecutors' decision on Monday. Echavarria's current attorney, Leslie O'Brien, did not immediately return a call seeking comment.