Police are responding to an incident at Balboa High School after a student on campus raised the alarm saying they have heard a single gunshot.
The school, together with nearby institutes James Denman Middle School, Leadership High School, and San Miguel Early Education School, were put on lockdown shortly after 7.30pm BST (11.30am local time).
The safety measure was taken by the police, with officers asking students to remain in their classrooms.
One person sustained a light injury, San Francisco Police Department (SFPD) have confirmed.
SFPD wrote on Twitter at 9.06pm BST (1.06pm local time): SFPD continues to investigate this incident at Balboa HS.
“Currently there is no active threat.
“One person sustained a non-life threatening injury during this incident.
“Two people have been detained, and one firearm has been recovered.”
Two suspects and a gun found on the campus of Balboa High School are in custody, SFPD added.
SFPD had previously tweeted: “An incident has occurred at Balboa HS.
“#SFPD is on scene.
“Balboa HS, James Denman MS & Leadership School are on lockdown at this time.”
SFPD spokesperson Grace Gatpandan said they could not confirm whether the firearm had been discharged.
A video shot by local media shows two teens being taken from the school in custody by the SFPD at approximately 9pm BST (1pm local time).
The San Francisco Unified School District sent out text and email alerts at about 8.07pm BST (12.07pm local time) notifying parents an incident was taking place at the high school.
The message said that students were safe and the police department was investigating.
Following the announcement, anxious and worried parents started gathering outside the school affected by the lockdown.
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