U.A.W. files labor charges against Trump and Musk over interview.

The United Automobile Workers union filed charges with federal labor regulators on Tuesday accusing former President Donald J. Trump and Elon Musk of threatening workers during a livestreamed conversation a day earlier.

The union, which has backed Vice President Kamala Harris, accused Mr. Trump of violating the law by voicing support for the practice of firing workers when they go on strike, an approach the former president suggested Mr. Musk had embraced.

In the glitch-delayed conversation on X, Mr. Trump described Mr. Musk as the “greatest cutter” of workers. He claimed Mr. Musk has responded to striking workers by saying, “That’s OK — you’re all gone.” Mr. Musk, the billionaire leader of Tesla and SpaceX, laughed in response, but did not directly address Mr. Trump’s remark before the former president changed the topic.

While Mr. Musk does have a reputation as a ruthless job-cutter — particularly at X, formerly Twitter, where he laid off roughly half the work force shortly after buying the company — and has been found to have engaged in anti-union tactics, Mr. Trump may have conflated different episodes across Mr. Musk’s business empire. Mr. Musk was found by the National Labor Relations Board in 2021 to have illegally fired a single Tesla employee for engaging in union activity. The board also accused him this year of illegally firing employees at SpaceX, but that involved a letter the workers circulated that was critical of Mr. Musk.

The N.L.R.B. said it had received unfair labor practice allegations against Mr. Trump’s campaign and Tesla. Regional offices for the board will investigate, said Kayla Blado, an N.L.R.B. spokeswoman.

Tesla did not immediately respond to requests for comment. On X, Mr. Musk insulted Shawn