A former Tesla worker is suing the car company, alleging he was called the N-word and describing the Fremont, California, factory as a "hotbed for racist behavior."
The San Jose Mercury News reported that Marcus Vaughn filed the discrimination suit on Monday. He was fired last month.
The assembly line worker says supervisors and co-workers routinely used the racial slur against him and other black employees, but no investigation was conducted, even after he made a written report to Tesla human resources.
The suit also claims Tesla CEO Elon Musk wrote a memo in May urging people to be "thick-skinned" about insults if an apology is delivered.
Three other black workers filed similar legal action earlier this year.
A message seeking comment from Tesla wasn't immediately returned.