The US state of California is reeling from its third mass shooting in eight days after a man shot dead seven former co-workers south of San Francisco.

The attacks took place in the coastal city of Half Moon Bay. The victims were all Chinese-American farm workers.

Suspect Zhao Chunli, 67, was arrested after driving to a police station.

It comes as the state mourns the death of 11 at Monterey Park - about six hours south east of Half Moon Bay - during Lunar New Year celebrations.