The Sonora Elementary School campus is back on schedule after going on lockdown this afternoon when police received reports of shots fired.
Parents are allowed on and off campus, said Principal Chris Boyles.
Police are still investigating the report.
School employees said a teacher who'd stepped away from class reported hearing shots fired shortly before noon. The noise appeared to come from behind a fence on the school's north side.
Principal Chris Boyles was notified. Classrooms were locked down. Later, first graders were escorted to a locked down cafeteria where they ate lunch.
They were held there until the campus was cleared shortly before 1 p.m.
At the request of the Sonora Police Department, Sonora Union High School District's alternative education campus was also placed on lockdown from 12:20 p.m. to 1:00 p.m.