Hollywood High School was temporarily on lockdown Tuesday morning after reports of an active shooter on campus that turned out to be a hoax, officials said.

Around 9:45 a.m., Los Angeles school police received reports from the L.A. Police Department about an active shooter at the campus, located at 1521 N. Highland Ave.

The school was placed on lockdown and officers from both departments searched the school trying to locate victims or a possible suspect, but none were found, officials said.

All students were deemed safe and the school returned to normal operations.

“Non-credible hoaxes are a serious offense that Los Angeles Unified takes seriously,” Supt. Alberto Carvalho said in a statement. “Threats disrupt the educational environment, increase stress levels and interfere with law enforcement’s ability to protect schools from real dangers. It also poses a serious risk to our community, draining resources and occupying the time of critical first responders.”

No further details about the incident have been released.