Tesla Chairman and Chief Executive Elon Musk has rubbished claims made on Thursday that workers in the car company's California branch had been underpaid, overworked and often suffered preventable injuries.
Jose Moran alleged in a Medium post that "excessive mandatory overtime", frequent injuries and below average hourly pay were hallmarks of the San Francisco Fremont plant in which all of Tesla's cars are manufactured.
"Frankly, I find this attack to be morally outrageous. Tesla is the last car company left in California, because costs are so high," Elon Musk said in a direct message on Twitter via Gizmodo.
Moran also accused the car company of attempting to silence its own employees in an effort to prevent them from forming a workers union.
"Many of us have been talking about unionizing, and have reached out to the United Auto Workers (UAW) for support... But at the same time, management actions are feeding workers' fears about speaking out," Moran said in the Medium post.
"Recently, every worker was required to sign a confidentiality policy that threatens consequences if we exercise our right to speak out about wages and working conditions," he added.
No leg to stand on
Musk rejected all the claims made in the blog post in his direct message to Gizmodo. In addition, he also questioned the authenticity of the worker making the claims against Tesla.
"Our understanding is that this guy was paid by the UAW to join Tesla and agitate for a union. He doesn't really work for us, he works for the UAW," Musk suggested.
"Tesla is the last company left in California, because costs are so high. The UAW killed NUMMI and abandoned the workers at our Fremont plant in 2010. They have no leg to stand on," he concluded.
In a statement sent to CNBC, the UAW slammed the allegation that Moran was paid by the union as "fake news."
"Mr. Moran is not and has not been paid by the UAW," the statement said.
"We would hope that Tesla would apologise to their employee, Mr. Moran, for spreading fake news about him.
"We can confirm that Mr. Moran and others at Tesla, have approached the UAW and we welcome them with open arms."
CNBC contacted Tesla on Friday, however, a spokesperson was not available for comment at the time of publication.
Clarification: This story has been updated since first published to include the statement from the UAW.
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