Authorities respond to shooting at YouTube headquarters

Officers run toward a YouTube office in San Bruno, Calif., Tuesday. Police and federal officials have responded to reports of a shooting Tuesday at YouTube headquarters in Northern California. (AP Photo/Jeff Chiu)

SAN BRUNO, Calif. — A woman opened fire with a handgun Tuesday in a courtyard at YouTube headquarters, wounding three people before fatally shooting herself in what is being investigated as a domestic dispute, authorities said.