MOUNTAIN VIEW, Calif. (AP) — Police say a 38-year-old man has died after being shot multiple times during a concert at a popular Silicon Valley music venue.

Mountain View police spokeswoman Shino Tanaka said the shooting happened backstage at Shoreline Amphitheatre, where Pittsburgh rapper Wiz Khalifa performed Friday night. The unidentified victim died at a local hospital Saturday. Police rushed to the outdoor venue after receiving multiple calls that shots had been fired, but officers are still looking for a male suspect believed to be in his 20s. They are asking concertgoers for photos or videos that might provide clues.

Tanaka tells KTVU-TV (http://bit.ly/1BOuxnh ) that authorities don’t yet know how a gun made it into the amphitheater, where patrons undergo security screening.

Wiz Khalifa has a performance scheduled for Saturday night in Chula Vista, California.