A woman opened fire with a handgun at the YouTube headquarters in California, wounding at least four people before killing herself.

After receiving multiple 911 calls reporting gunfire, local police and federal agents swarmed the company's complex. Police have yet to release details on the suspect or what might have motivated the shooting rampage. But MSNBC reports investigators believe a woman in her 30s approached an outdoor patio and dining courtyard at the building around lunchtime and began shooting, before entering the premises. There are also reports one of the wounded is the shooter's boyfriend. Three of the injured are being treated at a nearby hospital in San Francisco. Sources say the shooting had no links to terrorism.