Representatives from several US industries have turned against the two billionaires.
Members of the United Automobile, Aerospace and Agricultural Workers (UAW) union want to sue Donald Trump and Elon Musk.
The businessmen are accused of attempting to threaten and intimidate workers, according to a statement on the organization's website .
UAW officials seize on Trump's stance on labor strikes.
The US presidential candidate believes that such employees should be fired, and Musk supported his opinion in a recent interview.
The UAW reminded that participation in a strike is a worker's right. And dismissal for this or threats are punishable by law. Because of this, the union filed a lawsuit against Trump and Musk.
It's unclear how far this will go. But Trump has faced a number of lawsuits in recent times.
