Arvin High School in California is currently on lock down after reports of man with a gun nearby. No shots have been reported. Police are currently clearing classrooms one by one and all other areas of the school as well. So far, no gunman has been found.
I will update you as more information is available.
See videos below of students on lock down, the live police scanner and news broadcasts:
UPDATE: Police have cleared the school. No gunman was found. Students are being released to parents.