There were no convictions in the trial of four inmates charged with murder in the 2017 prison uprising at the James T. Vaughn Correctional Center.
It took the jurors five days before acquitting Abednego Baynes and Kevin Berry, on all charges from the riot that saw the death of correctional officer Steven Floyd.
Meanwhile, the jury could not reach verdicts on riot and assault for John Bramble or Obadiah Miller.
They were acquitted on all other charges.
WBOC reports that prosecutors must now decide if they will retry the two.
Deputy Attorney General John Downs declined comment.
All four defendants told the jury that they were innocent when they took the stand.
This is the second of the trials stemming from the prison riot.
Corrections Department Disappointed
WILMINGTON, Del. (AP) - The commissioner of Delaware's Department of Correction says he's disappointed that a jury delivered no guilty verdicts against four inmates charged in the fatal prison uprising in February 2017.
Commissioner Perry Phelps said in news release Monday that the department is disappointed but respects the jury's decisions.
He says he's grateful for the work of Delaware State Police and the Department of Justice which "tirelessly pursued justice on behalf of our fallen officer." He was referring to Officer Steven Floyd, who died during the 18-hour standoff.