An Irish man was apparently shot dead after he rammed his tractor through a neighbor's gate.
John Michael O'Sullivan, 47, originally from County Kerry, was shot dead in Fiddletown in Amador County, around 45 miles from Sacramento, the state capital.
Police have arrested O'Sullivan's neighbor, Kenneth John Zimmerman, 56, of Fiddletown, on suspicion of murder.
Police say there was a longstanding dispute between the two.
On Sunday, Zimmerman rang emergency services to report that O'Sullivan had rammed the tractor through his gate, smacked him in the face and then tried to run over him with the tractor.
The 911 tapes show that Zimmerman said the police had "better hurry up ... before I shoot him."
The police then received another call, this time from O'Sullivan's wife, who reported hearing gunshots and said she couldn't find her husband.
Police found O'Sullivan dead in his tractor with gunshot wounds.
The Department of Foreign Affairs said it has been in touch with Mr O'Sullivan's family.