National Rifle Association President Oliver North has been ousted after an alleged extortion scheme within the group’s highest-ranking officials came to light on Friday. In a statement, North told the organization he was “informed” he would not be nominated for reelection. North’s term ends Monday.

The NRA’s chief executive, Wayne LaPierre, wrote a letter to the board Thursday accusing North of plotting to remove him from the group by threatening to release to the board “damaging” information about LaPierre. He claimed North, a former Marine Corps lieutenant colonel perhaps best known for his role in the Iran-contra affair, was pressuring him to resign over alleged financial transgressions.

“Delivered by a member of our Board on behalf of his employer, the exhortation was simple: resign or there will be destructive allegations made against me and the NRA,” LaPierre wrote in the letter, which was published Friday by the Wall Street Journal.

“I believe our Board and devoted members will see this for what it is: a threat meant to intimidate me and divide us,” he continued. “I choose to stand and fight, and hope to bring 5 million members with me.”

LaPierre, the NRA’s executive vice president, who has been with the organization for decades, said he refused to comply with the threat, adding that he was “alarmed and disgusted” by the situation.

On Saturday, at the NRA’s annual meeting in Indianapolis, Richard Childress, a vice president at the NRA, read what amounted to a resignation letter from North that announced and explained his departure.

“Please know I hoped to be with you today as NRA president endorsed for reelection,” North wrote. “I’m now informed that will not happen.”

North continued his resignation letter by saying he believes the NRA should establish a committee to review the organization’s finances, which he said constitute a “clear crisis” that “needs to be dealt with” if the NRA wants to continue to be a viable organization.

The NRA’s board, comprising 76 members, is scheduled to meet Monday.

North’s departure and the circumstances surrounding it cast a public light on the apparent discord within the influential gun rights group.

The Wall Street Journal reported that North, who became NRA president last year, defended himself in a letter to the board Thursday, indicating his actions were “for the good of the NRA.” North previously wrote a longer letter to the board’s executive committee, alleging LaPierre had made more than $200,000 of wardrobe purchases and charged them to a vendor.

Sources familiar with the matter told the Journal that LaPierre’s Thursday letter was an “angry reaction” to North.

The back-and-forth is apparently fueled by a growing rift in a decades-long relationship between the NRA and the advertising agency Ackerman McQueen, according to the Journal. The NRA filed a lawsuit against Ackerman McQueen this month in Virginia alleging the firm had not been transparent in justifying its billings. In a statement to the Journal, Ackerman McQueen argued it was complying and called the lawsuit “frivolous, inaccurate and intended to cause harm to the reputation of our company.”

The suit specifically mentions a contract between Ackerman McQueen and North, the Journal reports, who was hired by the agency last year to host an NRATV documentary program, which LaPierre says nets him “millions of dollars annually.”

LaPierre detailed a phone call between one of his staff members and North that took place Wednesday, in which North allegedly suggested Ackerman McQueen was prepared to release an “allegedly damaging letter to the entire NRA board.”

“The letter would contain a devastating account for our financial status, sexual harassment charges against a staff member, accusations of wardrobe expenses and excessive staff travel expenses,” LaPierre wrote. “But then, Col. North explained the letter would not be sent — if I were to promptly resign as your Executive Vice President. And, if I supported Col. North’s continued tenure as president, he stated he could ‘negotiate’ an ‘excellent retirement’ for me.”

The NRA did not respond to a request for comment.

LaPierre wrote that after the call, he was informed by others he “needed to withdraw the NRA lawsuit against [Ackerman McQueen] or be smeared.” An Ackerman McQueen spokesman declined to comment to the Journal.

LaPierre went on to assert the claims made by the advertising firm were “conveniently” fabricated and brought up amid the lawsuit and demands from the NRA for accurate books and records.

The turmoil was publicized on the same day President Trump spoke at the NRA’s annual meeting in Indianapolis.

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