STILLWATER, Minn. – A seven -hour prisoner protest against conditions at Stillwater State prison ended when all but two prisoners returned to their cells. A state Corrections Department spokesperson, Andy Skoogman, said the situation throughout the day was “calm, peaceful and stable.” The emergency lockdown, Skoogman said, was standard procedure in such a circumstance. The same with the activation of a crisis negotiation team and a state-level special operations response team. The response team never entered the unit where the protest occurred, he said. No one was injured.

Earlier: Prison in lockdown after inmates stage sit-down

Among Stillwater incidents

> 2008: Four inmates attempted to tunnel their way out with pilfered tools, including an electric hammer drill. They made it 25 feet guard followed a power cord to the tunnel.

> 2013: An insider tipped guards that an inmate was was planning to fake a suicide attempt and escape when an ambulance would be called to take him to a hospital.

> 2018:  An inmate serving 29 years for murder struck a guard repeatedly in the head with a hammer and killed him.