FULLERTON, CA — A bomb threat was reported at an Orange County hospital Monday afternoon, authorities said.

The bomb threat was reported to Providence St. Jude Medical Center Tuesday morning at around 2 p.m. by an anonymous caller, according to the Fullerton Police Department.

Officers initiated a shelter-in-place at the hospital as a part of the investigation, and after an extensive search, no explosives were found in or around the hospital.

The incident remains under investigation as detectives work to identify the source of the call.

No further information was immediately available.