A US jail has been placed under an emergency lockdown after about 100 prisoners refused to return to their cells.
Members of a crisis negotiation team are at the prison in the state of Minnesota.
A spokesperson for the state’s Department of Corrections said on Sunday the special operations response team had been deployed “out of an abundance of caution”.
The reason prisoners were refusing to return to their cells at one of the facility’s living units remained “unclear”, according to the spokesperson.
No injuries had been reported and two officers at the Stillwater correctional facility were said to be safe in a secure control area.
They are in contact with facility staff and the spokesperson added the situation was “currently stable”.
Just over 1,200 inmates are at the facility to the southeast of Stillwater, according to department records.
The facility, which was built in 1914, is the state’s largest close-security institution for men.
There is a total of seven living units at the facility, according to the Department of Corrections’s website.
The website notes the facility’s role is to provide men with “educational, vocational and industrial programming opportunities during incarceration”.