A shooting at a southern California university has left at least four wounded, including one critically, the Los Angeles Times reports.

Law enforcement say person targeted at the University of Southern California Halloween party was in surgery for critical injuries on Thursday.  Another three bystanders were also struck but face non-threatening injuries.

USC has placed the campus in a state of lockdown, though police officials said the shooting was not directly related to the university itself.

"Police-related incident in progress at Tutor Campus Center on USC Campus. The scene is secure and there is an ongoing investigation. Campus shut down, stay away from area at this time," a university statement to students and parents read.

A student speaking to the Los Angeles Times on condition of anonymity, said at least 100 people were in attendance at the overcrowded party thrown by a student group.

In May two men were arrested and charged for the killings of two graduate students a few miles from the USC campus a month prior.

Bryshon Nellum, USC sprinter turned Olympic medalist, was shot in the leg three times at Halloween party during his second year at the university in 2008.

In April, a former student at a northern California university was arrested for killing seven people at a small Christian school in the city of Oakland.

In 2011, two people were killed in a shooting at Virginia Tech, the site of the a 2007 attack that left 33 dead and became the deadliest mass shooting in modern US history.

Source: Agencies