Students have been released from class following a safe and secure campus measurein response to an unconfirmed threat of a weapon on campus, officials said.

El Cajon Police put the school on lockdown Tuesday morning after reports of a weapon on campus, according to the school district. Students were released from Period 6 classes, the district said, and students with a Period 7 class will remain on campus until the regular 2:48 p.m. release. Two canines assisted police in searching, the district said.

Regular teaching and classroom activities were taking place, the alert said, behind closed and locked doors and all students are safe.

No one was allowed on or off campus.

No further details were immediately available.

This is a developing story. Check back for updates.