A day after the National Rifle Association filed a lawsuit saying its reputation had been smeared by its most prominent contractor, that contractor claimed in its own filing that it had been smeared by the NRA.

The dueling claims escalated the legal battle between the NRA and Ackerman McQueen, an advertising firm that has worked with the gun group for nearly four decades. The bitter split between the organizations sparked a recent power struggle between Wayne LaPierre, the NRA’s chief executive, and Oliver North, an Ackerman employee who was ousted as the NRA’s president last month.

Ackerman is seeking $50 million in the counterclaim it brought Thursday in state court in Virginia, a filing that was previously reported by The Daily Beast. The NRA, in two separate lawsuits against Ackerman, had accused it of refusing to fully cooperate with an audit, defaming LaPierre and breaching confidentiality agreements.

Ackerman rebutted those allegations in its lawsuit, saying that it had “complied with every audit” requested by the NRA — including one in February — and that it itself was defamed by the gun group.

It also accused the group’s outside lawyer, William Brewer, of sharing “misleading information,” although redactions left it unclear what was being described in that way. Ackerman said its business had been harmed by an article that appeared in The New York Times in March, which included the first report that North, then the NRA’s president, had a financial contract with Ackerman.

Brewer called the legal filing “a misguided attempt to deflect attention from Ackerman McQueen’s numerous failures to comply with its obligations,” adding that its claims emerged only after the NRA “sought to compel the agency to provide documents and billing records.”

Ackerman declined to comment.

The closeness of the organizations over the years has made the rift all the more shocking. Ackerman has given the gun group a voice going back to the “I’m the NRA” campaign in the 1980s. LaPierre’s wife, Susan, once worked for the firm, and its top executive in the Washington area, Tony Makris, is a former business associate of LaPierre. On top of that, Brewer is the brother-in-law of Ackerman’s chief executive.

Ackerman also continues to operate NRATV, the NRA’s hard-edged online streaming service.

The legal fight is connected to an investigation into the NRA’s tax-exempt status by Letitia James, the attorney general of New York. Amid threats by James last summer to investigate, the NRA began auditing contractors, and it has said Ackerman refused to fully cooperate, although Ackerman disputed those claims in its latest filing.

Ackerman also said the NRA’s lawsuit last month “was not legally and properly authorized by the NRA board” as required by New York law.

Leaks have angered both sides. North held a typically ceremonial post as NRA president but had an Ackerman contract said to be worth millions of dollars. LaPierre billed $275,000 for purchases at a menswear boutique in Beverly Hills, and $267,000 on personal expenses, including travel to the Bahamas, Florida, Nevada, Budapest and an Italian lake resort.

With the NRA facing scrutiny over its finances and emboldened opposition from gun control groups, Ackerman said the organization had been “highly effective in turning the spotlight away from the NRA’s troubles.”

This article originally appeared in The New York Times.