Four people, including a child, were killed when a suspect opened fire in a Southern California office building Wednesday evening, police said.

The shooting occurred in Orange, California, about 30 miles south of Los Angeles, around 5:30 p.m. local time, the Orange Police Department said.

The suspect and a woman were injured with gunshot wounds during the shooting, Lt. Jen Amat said. Both were hospitalized and in critical condition. It was unclear whether the suspect's gunshot wounds were self-inflicted or from police, Amat said.

Details about what happened were scarce early Thursday. The shooting comes just a week after a gunman in Boulder, Colorado, killed 10 people at a supermarket. The week before that, a gunman in the Atlanta-area killed 8 people, most women of Asian descent, at three spas.