San Bernardino County sheriff's deputies said it all started with several kids fighting around 6 p.m.
The violence escalated into gunfire near the Cinemark movie theater.
At least one person, possibly a juvenile, was shot and rushed to the hospital, deputies said. The mall had to be evacuated.
Photos from the scene show doors with broken glass at the theater.
There was no word on whether anyone was taken into custody, but deputies said it was not an active shooter situation.