Manhunt underway for gunman who opened fire at US high school

A manhunt is underway for at least four men who opened fire outside a San Francisco high school.

Four people were injured, including one female student who is in a critical condition, when gunfire broke out on Tuesday afternoon.

Students initially thought the incident was a joke until the school was placed into lockdown, CCN reports.

Police said it was not a random shooting and the female victim may have been targeted.

ABC News America reports the wounded students ran into the school after they were shot and four male suspects wearing dark jeans and hoodies were seen running away.

“It was crazy, I just saw people running and I heard shots going off,” student Diego Oritz told ABC.

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