Former Vikings punter Chris Kluwe accused an assistant coach of being a "bigot" and called then-coach Leslie Frazier and General Manager Rick Spielman "cowards" Thursday in a scathing article he penned for the website Deadspin.

Kluwe wrote that he believes he was released by the organization last spring largely because of his social activism, specifically his outspoken support of same-sex marriage. Kluwe reserved his harshest criticism for Mike Priefer, the Vikings special teams coordinator whom Kluwe accused of making gay slurs.

In his article, Kluwe described exchanges with Priefer during the 2012 season.

"[Priefer] would ask me if I had written any letters defending 'the gays' recently and denounce as disgusting the idea that two men would kiss, and he would constantly belittle or demean any idea of acceptance or tolerance," Kluwe wrote.

Kluwe also recalled a remark by Priefer before a special teams meeting: "As we sat down in our chairs Mike Priefer, in one of the meanest voices I can ever recall hearing, said: 'We should round up all the gays, send them to an island, and then nuke it until it glows.'"

Priefer issued a statement which read, "I vehemently deny today's allegations made by Chris Kluwe. I want to be clear that I do not tolerate discrimination of any type and am respectful of all individuals. I personally have gay family members who I love and support just as I do any family member. The comments today have not only attacked my character and insulted my professionalism, but they have also impacted my family."

'I have witnesses'

In his article, Kluwe also cited specific conversations with Frazier and Spielman in which they asked Kluwe to refrain from speaking out on social issues.

The Vikings released a statement Thursday afternoon saying the organization takes Kluwe's allegations "very seriously and will thoroughly review this matter. … We do not tolerate discrimination at any level."

Frazier, who was fired Monday, declined to comment in a text message. An NFL spokesman said the league had no comment.

Contacted after his article was published, Kluwe said he stands by everything he wrote.

"I have witnesses," he said. "I prefer not to call any witnesses unless it's legally needed because those are my friends and teammates and I'd like to keep them out of it."

Several Vikings players, including fullback Jerome Felton, punter Jeff Locke and safety Harrison Smith, quickly jumped to Priefer's defense on Twitter. Kicker Blair Walsh, who was an All-Pro with Kluwe as the holder in 2012, issued a statement saying of Priefer, "His professionalism in the workplace is exemplary, and I firmly believe that my teammates would wholeheartedly agree."

Career likely over

Asked if he's considering a discrimination lawsuit, Kluwe said in a text: "No idea yet. Would rather not, but that depends on what happens going forward."

Kluwe, who is not employed by a team now, wrote on Deadspin that he hopes his article prevents Priefer from coaching in the NFL, a point he reiterated in a phone interview.

"I kept my silence for the entire year," he said. "I wasn't going to bring that on the team during the year. Now that it's pretty obvious that I'm not going to get another shot in the NFL, I feel like it's a story that needs to be told."

The Vikings released Kluwe in May after drafting Locke in the fifth round. Kluwe was 31 years old and was scheduled to make $1.45 million. He signed with Oakland but did not make the team out of training camp. He had tryouts with several other teams but was not signed. He acknowledges that his NFL career is likely over, but he's not worried about the fallout.

"I realize there will be people that say, 'This is just sour grapes. He's upset that he got cut,'" he said.

Vikings respond

In their statement, the Vikings said they supported Kluwe's activism and that he was released for performance reasons only.

"The team has long respected our players' and associates' individual rights, and, as Chris specifically stated, Vikings ownership supports and promotes tolerance, including on the subject of marriage equality," the statement read. "Because he was identified with the Vikings, Chris was asked to be respectful while expressing his opinions. Team ownership and management also repeatedly emphasized to Chris that the Vikings would not impinge on his right to express his views.

"Any notion that Chris was released from our football team due to his stance on marriage equality is entirely inaccurate and inconsistent with team policy. Chris was released strictly based on his football performance."

In his article, Kluwe noted that owner Zygi Wilf approached him before a game and praised him for his public support of gay marriage.

"I'm wondering if possibly Frazier thought that maybe I had gone over his head to go talk to the owner," Kluwe told the Star Tribune. "But that was completely out of the blue. I was just warming up before the game and Zygi came up and talked to me and said that. I was like, 'Wow, that's awesome.' "

Kluwe