A protest Sunday at the Stillwater prison in which roughly 100 inmates refused to go back to their cells has resolved peacefully, the Department of Corrections said.

The demonstration started around 8 a.m., and all inmates were back in their cells by 4 p.m., DOC spokesman Andy Skoogman said in a news release.

5 EYEWITNESS NEWS received numerous tips about the situation Sunday morning, both from inmates and from loved ones of incarcerated people. They say the action was a peaceful demonstration because of the living conditions at the prison.

“They’re not aggressive, and they don’t want to hurt or harm any of the staff, any of the officers or anyone that’s involved,” said Marvina Haynes, whose brother, Marvin Haynes, is incarcerated at Stillwater prison. “What they want is to have access to clean showers and clean water.”

Activist group Communities United Against Police Brutality backed up those claims, saying frustrations had boiled over due to a “lack of access to clean water,” ice or showers for days because of short staffing.

Skoogman acknowledged inmates had limited access to showers due to “modified cell release schedules” brought on by “staffing challenges” but said any claims of inadequate clean water are “patently false.”

AFSCME Council 5 leadership, representing corrections officers, issued a statement Sunday calling the incident “endemic,” adding that “chronic understaffing” has resulted in restricted programming and upset inmates.

“Our union believes to our core that our correctional facilities cannot have transformational offender programming without sufficient facility security, we can and must have both,” said Bart Anderson, interim executive director of AFSCME Council 5.

DOC Commissioner Paul Schnell said about 100 out of 225 inmates in a particular housing unit refused to return to their cells, remaining peaceful and continuing their activities, like playing cards.

Getting the offenders back in their cells all happened through negotiations, Schnell said.

“Never was there any deployment of any type of gas. Never was there a need for a type of entry by any of our tactical teams,” Schnell said.

No inmates or prison staff were harmed. Schnell says two inmates were taken to isolation cells but didn’t expand on why.

The prison will remain on lockdown through the holiday weekend.