A Rancho Santa Margarita high school was closed Wednesday afternoon, hours after the campus received a threat, authorities said.
The threat to Santa Margarita Catholic High School came mid-morning. After consulting with the Orange County Sheriff's Department, administrators decided to close the campus and cancel after-school activities.
Carrie Braun, a spokeswoman for the Sheriff's Department, said there was no immediate risk to students. She did not reveal the nature of the threat or how it was delivered, and said no suspect had been identified.
Campus officials posted an alert on the school's website saying students must leave campus by 3 p.m. so authorities could conduct an investigation. A boys CIF basketball game set to be held on campus was postponed.
"At this time, we are optimistic the investigation will be concluded this evening and that school will be in session tomorrow," administrators said in the alert.
About 1,700 students are enrolled at the school.