The students - both 15-year-old boys - were arrested and are now facing charges.
MONTCLAIR, Calif. (KABC) -- Two 15-year-old students at Montclair High School were taken into custody Thursday morning after one of them was captured on video holding a magazine with ammunition, officials said.
According to a statement issued by the Chaffey Joint Union High School District, authorities notified the school about the video and police immediately reported to the campus.
They noted the student was not holding an actual gun in the video.
Police say the student seen in the video was located and detained without incident. The student told investigators that another student was currently in possession of the magazine, according to police.
Investigators went searching for that second student, who was also detained without incident.
Police said the second student had the magazine in his waistband.
"It was learned the loaded magazine was located several months prior in another city and the student decided to bring it to the school," read a press release issued by police.
Both students are teen boys, according to investigators, who told police there were no firearms involved. Police said no actual guns were found during their search of the campus.
School officials issued a complete lockdown at the campus located at 4725 Benito St. which was cleared after the students were taken into custody.
No students or staff members were injured.
Police said both students were arrested and transported to the San Bernardino County Juvenile Detention Center, where they were booked for possession of ammunition on school grounds and being minors in possession of live ammunition.
The incident remains under investigation.