TWENTYNINE PALMS, Calif. (AP) — An accidental discharge of a weapon put a U.S. Marine Corps training center in the Southern California desert on lockdown for several hours Monday, a base statement said.

No injuries were reported in the incident at the vast Marine Corps Air Ground Combat Center located at Twentynine Palms, 125 miles (201 kilometers) east of Los Angeles.

The statement said the incident remained under investigation. It gave no details of who was involved in the the inadvertent discharge, where it occurred and the type of weapon.

A shelter-in-place order was lifted at 12:20 p.m.

“The installation is secure and base personnel are free to resume activity,” the statement said.

The base earlier reported that an anonymous report of shots fired was received at 8:52 a.m. and a lockdown was implemented.