Anaheim police received a call shortly before 6:30 a.m. about shots heard near the school - not on school grounds - and the school was placed on lockdown as a precaution.
The department said on Twitter that school staff members reported "all is well at the school and all students that are at the school this early are safe."
At 8:19 a.m., Anaheim police tweeted the "all clear," saying investigators did not find any evidence of a crime. The lockdown was lifted, and students resumed school activities.