UPDATE (April 10, 1:55 p.m.)
Police are investigating a threat made to the California City Middle School and are present on campus "as precaution."
Cal City Police say there will be extra police officers on all school campuses while they investigate a telephone threat to "shoot up the middle school."
As of noon, all Cal City schools were on modified lockdown, however classes are resuming under the lockdown.
Officials say many parents have picked up their kids from school.
Check back for details.