A Greek prison shooting Saturday saw 11 inmates escape and two people injured.
Gunmen stormed the prison near the central Greek city of Trikala at 8:30 pm, firing automatic weapons and throwing grenades.
It is believed there were about six gunmen who carried out the attack.
They arrived at the front gates in a van and a pick-up truck and began shooting.
"During the exchange of heavy fire that lasted over half an hour and turned the area into a battlefield, two perimeter guards were injured in the abdomen, one of them seriously," a Justice ministry official said.
The escapees descended from the prison windows using bed sheets and climb over barbed wire fences to exit the facility during the mayhem.
The attackers got away, while police locked down the prison after a night-long standoff with inmates.
Authorities said that two of the seven grenades thrown remain unexploded and will be disposed of.
It is still unclear who the gunmen were trying to free.
Last month a nearby prison saw an unsuccessful attempt at freeing a notorious Greek crime boss using a helicopter that lowered a rope into the yard.
The helicopter was forced to land after being hit by gunfire.