OMAHA, Neb. (AP) — A power outage forced a lockdown at the Douglas County Jail in Omaha, and no escapes have been reported.

The jail and several dozen other Omaha Public Power District customers lost power in a section of downtown late Wednesday morning. The main grid had been taken offline for planned maintenance, but the backup circuit failed.

The jail’s generator started up but sputtered to a halt after 30 minutes because of a mechanical problem.

The jail was without power from a little after 11 a.m. until a little before 2 p.m.

Douglas County corrections director Mark Foxall says inmates were kept secure.