The federal government is taking a closer look at Tesla for its efforts to resist a union drive organized by factory employees who say that they are overworked.

The National Labor Relations Board issued an official complaint to Tesla on Thursday, citing claims by workers that Tesla prevented them from leafleting or discussing union activity and worker safety on Tesla’s Fremont, Calif. factory premises. The charge sheet additionally alleges that Tesla HR staffers “interrogated” an employee about “protected” union activity.

Allegations that Tesla has taken potentially illegal actions against factory staff organizing with United Auto Workers follow strong pushback from Musk and Tesla leadership. After the union drive first went public with an open letter from a Tesla worker in February, Musk told employees in an email that UAW’s “true allegiance is to the giant car companies,” and that the union’s tactics were “disingenuous or outright false.”

Before an NLRB board complaint is issued, “a preliminary investigation,” is made by a board member into worker or union complaints filed with a regional NLRB office, according to former NLRB lawyer and People’s Policy Project founder Matt Bruenig. “Then a decision is made inside the regional board that goes up to regional manager, where they will have discussion among top officials and the board agent about whether or not there’s a decent likelihood of success.”

In an emailed statement to VICE News, posted in full below, a Tesla spokesperson called the allegations “entirely without merit” and said that the “baseless [Unfair Labor Practice] filings” are “meant only to generate headlines.” The statement added that “there’s a certain irony in just how far the UAW has strayed from the original mission of the American labor movement.”

The Tesla workers organizing with UAW have said that Tesla works them too hard for too little pay, making work at the vaunted carmaker’s factory unsafe. OSHA figures collected in a May report show that Tesla has maintained a higher rate of non-fatal injuries than the national average in recent years.

Musk dismissed the complaints as coming from a loud but vocal minority. He has also told workers that factory injuries “break my heart” and that Tesla would be installing “free frozen yogurt stands” and “electric pod rollercoasters” around the factory.

The NLRB complaint contains five cases consolidated into one. Bruenig told VICE News that it contains significant “coercion charges,” as well as less serious charges regarding violations in Tesla’s employer agreements.

Should an administrative law judge find the charges “meritorious,” or in the more likely event of a settlement, Bruenig told VICE News that Tesla likely wouldn’t be fined. But if Tesla should violate the terms of a potential settlement or cease and desist order, Bruenig says that the workers case would then proceed to federal court, which could have far greater ramifications.

Here’s Tesla’s full statement on the NLRB complaint, and below that is the full complaint itself: