In a developing story, a shooting was reported Friday morning at Highland High School in Palmdale, Calif., the Los Angeles Sheriff's Office told Fox News.
Officials said they received a call about a man with a gun on the high school's campus.
First responders were on the scene.
Shots were first reported at about 7 a.m. local time, which is a half hour before school was set to begin, the Los Angeles County Sheriff's Office said.
Firefighter-paramedics told NBC Los Angeles they received a report of one person with a gunshot wound, though any injuries couldn't be independently confirmed.
CBS Los Angeles reported a person who was injured transported themself to the hospital.
No one is in custody, the sheriff's office said.
Highland High School is located about 65 miles from Los Angeles.
The school and other nearby schools are reported to be on lockdown.