Florida prison officials are trying to figure out whether a computer glitch may be behind two recent, as yet unexplained incidents where all of the doors at a facility’s maximum-security wing opened simultaneously. In the latest occurrence, on 13 June, guards at the Turner Guilford Knight Correctional Center in Miami, Florida, had to rush to corral prisoners back into their cells after a “group release” button in the computerized system was triggered. The entire facility, including locks on cell doors, surveillance cameras, water and electricity, and other systems, has been automated. Anyone who gains full access to the network—whether from a touch-screen monitor in the guard tower, or from outside, via a security hole—can control any of these functions. Guards say they don’t know how it happened, and recently released surveillance footage does not pinpoint the source of the errant command.