At least 4 people have been wounded in a shooting incident at a Halloween party at the University of Southern California (USC), in Los Angeles.

Campus news outlet Neon Tommy said the incident took place at 23:30 local time. Police confirmed that there were casualties.

At least one suspect has been detained.

The university shut down the campus and urged students to stay away from the area of the shooting, amid earlier reports of a gunman at large.

Witnesses reported a “mob of people” fleeing from the main campus building.

“Everyone started running. I saw a guy who was shot in the leg. He was limping and screaming for his friends to help him,” one witness said, quoted by the Los Angeles Times newspaper.

“People were screaming and running away.”

At least 4 people have been wounded in a shooting incident at a Halloween party at the University of Southern California

USC’s Department of Public Safety issued alerts asking students to stay away from the area, stay indoors and avoid opening the door to strangers.

In 2008, University of Southern California sprinter Bryshon Nellum was shot in the leg three times at a Halloween party just off the campus.

Bryshon Nellum recovered and won a silver medal in the 4 x 400 m relay at the London 2012 Olympics.

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