Authorities are trying to find out if an unhappy customer shot and killed an auto mechanic after a heated argument, according to CBS San Francisco.

Earlier this month, Jimmy Martinez credited his dog, Chata, for saving his life.

Martinez told CBS San Francisco, “If it wasn’t for the dog, I wouldn’t be here.”

But Martinez did not survive a second shooting Friday night and Chata couldn’t save him.

Oakland police say around 9:30 p.m. local time, someone shot Martinez outside of his RV after an argument. People living in nearby RVs heard the shots.

“I was about to eat and watch TV. And I heard like 10 shots,” said neighbor Marvin Morris.

Another neighbor, Duncan Burns, also heard gunfire.

“His dog is a super dog, wonder hero,” Burns said. “The dog was locked in the house, couldn’t get out to help.”

Martinez and his dog were still recovering from a December 4 shooting.

In December, Martinez said a truck driver shot him in the hand over a parking space, and Chata charged at the trucker and was shot in the nose.

His sister Diane told CBS San Francisco, “If it wasn’t for Chata, I wouldn’t be standing here, I would be planning a funeral for my brother.”

It’s still early, but it doesn’t appear the two shootings are connected. Martinez worked as a mechanic, fixing people’s cars on the street.

A witness said a few hours before the shooting, a customer blamed Martinez for a bad repair job and demanded a refund.

“They had a little argument, a confrontation for about 5-10 minutes. And then, the other gentleman drove off very angry,” Hyo Song, who works across the street from the scene, said.

Police are looking for the customer and they’re also looking at other leads.

For now, Chata is staying with Martinez’s sister.

She told the station that the dog was crying all night.

Picture courtesy of CBS/ AP