Officials declared a security emergency early Saturday morning after the locks of more than 500 cell doors at the Montgomery County Correctional Facility in Boyds, Md., simultaneously opened.
A computer malfunction caused the locks to open at the same exact time around 12:20 a.m. Saturday morning. Officials confirmed that no inmates had tried to escape during the hour it took to fix the glitch and secure the doors, CBS Baltimore reports.
About 20 additional police cars were called to create a perimeter while the problem was being fixed.
Arthur Wallenstein, director of the county’s Department of Corrections and Rehabilitation, told The Washington Post that the cell door locks also disengaged Tuesday. Officials are trying to determine the source of the problem in the system.