"Although Tesla stands out as a groundbreaking company at the forefront of the electric vehicle revolution, its standard operating procedure at the Tesla factory is pre-Civil Rights era race discrimination", the employees said in the complaint, that was filed in a California court.
Mr. Vaughn says he was sacked in October for "not having a positive attitude".
The email drew criticism from The Root as well as California Civil Rights Law Group attorney Larry Organ. Organ's law firm sued Tesla on behalf of other black employees this year.
In the suit, former assembly worker Marcus Vaughn, who said he was sacked from the electric vehicle maker for "not having a positive attitude", claims supervisors and co-workers called him the n-word, but his written report to human resources about it drew no investigation.
Vaughn's lawsuit is seeking class-action status and unspecified damages under California's anti-discrimination law.
"Although Tesla stands out as a groundbreaking company at the forefront of the electric auto revolution, its standard operating procedure at the Tesla factory is pre-Civil Rights era race discrimination", Vaughn's complaint to the court reads.
Demetric Di-az, his father, Owen Diaz, and Lamar Patterson, who also worked in the Fremont plant, alleged in the lawsuit that they were targets of 'racially motivated abuse, including the frequent use of racial slurs'. The lawsuit followed another one in October, when three employees made similar claims against the company. Jose Moran, apparently a former employee at the Fremont factory, wrote a biting piece about the facility and Tesla, stating that the company believes in "excessive mandatory overtime" and low wages.
Shares of Tesla closed down 2.1 percent on Tuesday afternoon following news of a civil rights lawsuit against the automakers.
'In situations where Tesla is at fault, we will never seek to avoid responsibility, ' the spokesperson said.
Tesla Factory in Fremont, California.
The growing number of discrimination lawsuits against Tesla come as the company is also facing a unionization campaign from the United Auto Workers.
Adding insult to injury is an email Elon Musk sent to factory employees on May 31, per Bloomberg.
The union and the worker denied that he had been paid by UAW. He was sacked last month. He said that he and other employees were considering unionizing and had reached out to UAW for help.