Prisoners at a police station in the south loop had to be transferred to another facility after an officer accidentally fired his gun inside the station.
It happened Monday night in the Central district station at 18th and State Streets.
The bullet hit the first floor ceiling, damaging a water pipe which then poured onto computers and desks.
No one was injured.
Police say the sergeant whose weapon discharged will likely face discipline within the department.
Water to the building was shut off overnight while repairs were made.