San Francisco, Mar 14 (IANS): Elon Musk-owned Tesla factory in the state of California saw 450 Covid-19 cases till December 2020 after it shut and then reopened the plant defying the public health order.

According to data from legal website PlainSite, the Alameda County Department of Public Health showed coronavirus cases at Tesla's plant in Fremont, California from May till December, while the factory was operational in March and April despite Covid-19 shutdown restrictions in place.

"Excellent lying skills. The Department very well knows that the factory was operational in March and April in violation of the multi-county-wide shutdown order," PlainSite said in a tweet.

"Note, it only started keeping track in May and it stops in December 2020," it added.

After the public health officials in Alameda County declared Covid-19 related measures as cases surged across the country, the Tesla plant was shut on March 23 under a six-county order in the San Francisco area.

But a few days later, the company again reopened the Fremont plant, even though it was in violation of the public health order.

Then US President Donald Trump backed Musk in his fight with the local authorities as he reopened the electric car factory against the state guidelines, defying the stay-at-home order in place and challenging the authorities to arrest him if he has defied the rules.

"Tesla is restarting production today against Alameda County rules. I will be on the line with everyone else. If anyone is arrested, I ask that it only be me," Musk had tweeted.

Musk called 30 per cent of workforce to resume duties at Tesla Fremont factory.

Tesla then filed a lawsuit against Alameda County over the shutdown order on May 9, but dropped the suit less than two weeks later.