San Francisco, Sep 24 (IANS): Elon Musk-run Tesla has countersued California Civil Rights Department (CRD), that alleged racial bias at the electric car-maker's US factory in a lawsuit.

Tesla alleged in its countersuit, filed in state court in Alameda County, saying the CRD adopted "underground regulations" in its investigations of its Fremont, California factory, reports TechCrunch.

The CRD had sued Tesla in February over allegations of Black workers being subjected to "mistreatment, harassment, unequal pay and a hostile work environment".

The electric car-maker had been trying to somehow convince the judge to dismiss the racial bias case but to no avail.

The Musk company alleged that the CRD violated state law by not seeking public comment before adopting procedures for investigating and suing employers.

The automaker has been accused of racial bias at its plants in the past.

In October last year, Tesla was ordered by a federal court to pay nearly $137 million as damages to a former employee who allegedly encountered racist abuse, discrimination and harassment at the company's plant in Fremont, California.

Owen Diaz, an elevator operator who worked for the company between June 2015 and May 2016, sued the carmaker, alleging a hostile work environment and racial harassment.

The jury asked Tesla to pay an additional $6.9 million for causing Diaz emotional distress.

Tesla's vice president of people, Valerie Capers Workman, had downplayed the allegations in the lawsuit.

"Diaz never worked for Tesla. He was a contract employee who worked for Citistaff and nextSource. Diaz worked as an elevator operator at the Fremont factory for nine months, from June 2015 to March 2016," Workman posted in a blog post.