The man who shot dead three co-workers before being killed by police Thursday had complained about racism at work and was recently notified about erratic driving on the job, his shop steward said.

Mike Ambrosio, who was shot in the arm, that he had confronted Shareef Allman less than a week ago about having turned over a truck and snagging overhead wires when he left the truck bed in the air at the quarry where they worked in Cupertino, Calif.

“He’s had so many accidents and always said that because he’s African American, the company was after him,” Ambrosio told the newspaper. “He was an unsafe driver.”

Ambrosio added that he told Allman last Thursday that “no one has ever had so many accidents in the company like you have.”

When Allman started shooting, Ambrosio said, he shouted: “You guys want to (expletive) with me? You want to (expletive) with me?”

Allman was on the run for a day before being cornered, shot and killed Thursday morning, law enforcement sources told NBC affiliate KNTV.

Allman was shot by police in the same Sunnyvale neighborhood that police had searched a day earlier.

The Santa Clara County coroner confirmed Thursday evening that Allman was the man killed by deputies, KRON television reported.

Three deputies were on routine patrol when they encountered a man crouched behind a vehicle in the driveway of a home, Santa Clara County Sheriff Laurie Smith said.