Two spectators at a men's rugby match at Diablo Valley College in Pleasant Hill were injured when one of them punched the other in the jaw, prompting that man to open fire with a gun, a campus official said Sunday.

The violence erupted at about 8 p.m. Saturday immediately after a game between the Diablo Gaels and the San Francisco Golden Gate Rugby Club, said college spokeswoman Chrisanne Knox. The Gaels rent facilities on campus but are not affiliated with the college, Knox said.