Wayne LaPierre, the National Rifle Association’s longtime leader, is resisting calls for his resignation.

In a fiery letter to the organization’s board sent Thursday afternoon, and obtained first by the Wall Street Journal, LaPierre said NRA President Oliver North had pressured him the previous day to step down. LaPierre refused.

LaPierre says North threatened the release of a letter with damaging information about the NRA.

“The exhortation was simple: resign or there will be destructive allegations made against me and the NRA,” states LaPierre’s letter.

“I believe the purpose of the letter was to humiliate me, discredit me, discredit our Association, and raise appearances of impropriety that hurt our members and the Second Amendment. The letter would contain a devastating account of our financial status, sexual harassment charges against a staff member, accusations of wardrobe expenses and excessive staff travel expenses.”

The internal turmoil comes on the heels of an investigation by The Trace and The New Yorker that exposed years of self-dealing and financial impropriety at the NRA’s highest levels. Staff Writer Mike Spies’ reporting showed that NRA leadership and preferred vendors had extracted hundreds of millions of dollars from the nonprofit’s budget.

According to The New York Times, North sent his own letter to the board saying that he had created a committee to examine accusations of financial wrongdoing at the organization. “I did this because I am deeply concerned that these allegations of financial improprieties could threaten our nonprofit status,” the letter read.

Many of those allegations center around Ackerman McQueen, the Oklahoma-based public relations firm central to the NRA’s messaging. Ackerman’s influence over the NRA has grown significantly over their three-decades-long relationship. Tax filing show the NRA paid the firm more than $40 million in 2017.

LaPierre has longstanding ties with Ackerman, and long fought for the firm’s involvement in the NRA’s business. One internal memos obtained by The Trace states that roughly a quarter of the NRA’s staff is “now managed by former employees” of the firm.

In a surprise move, the NRA filed suit against Ackerman earlier this month, alleging that the firm has denied the gun group access to basic business records.

“As most of you know, I’ve been a proponent of AM [Ackerman McQueen] in the past — because they are capable of doing high quality work. But as I’ve discovered, AM is capable of something much different,” LePierre writes in the letter.

The suit also disclosed that North’s $1 million annual contract is paid by Ackerman, not the NRA.

In his letter, LaPierre made it clear that he believed North was acting on behalf of Ackerman’s interests. “All of this is painful for me. I will not judge Col. North, but must report what many of you already know: he has contractual and financial loyalties to AM,” he wrote.

The power struggle comes amid the NRA’s annual meetings in Indianapolis. Hours before the letters surfaced on Friday afternoon, LaPierre and North shared a stage at the Lucas Oil Stadium. President Donald Trump and Vice President Mike Pence were also featured speakers.

On Monday, the NRA’s full, 76-member board of directors will convene for its annual meeting, where the conflicts between LaPierre and his detractors may culminate.

Read LePierre’s letter in full here: