The Vikings said in a statement that they take the allegations "very seriously and will thoroughly review this matter."
"As an organization, the Vikings consistently strive to create a supportive, respectful and accepting environment for all of our players, coaches and front office personnel," the team said. "We do not tolerate discrimination at any level.
"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. 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."
Kluwe called Priefer "a bigot" and Spielman and Frazier "two cowards" for releasing him in May after eight seasons with the Vikings.
He was due to make $1.45 million, which was more than the cap-strapped Vikings wanted to spend on a punter. So they drafted Jeff Locke in the fifth round and parted ways with Kluwe, bringing to an end his colorful and outspoken stay in Minnesota.
"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," the Vikings said Thursday. "Chris was released strictly based on his football performance."
In his article, Kluwe alleged that Priefer grew more and more impatient with the various causes Kluwe supported and several times made anti-gay remarks during team meetings.
Kluwe said wanted to post his article now in hopes of discouraging the Vikings, or any other team, from employing Priefer, who is widely respected at Vikings headquarters and is viewed by some as a potential head coach one day. Priefer was hired by the Vikings in 2011. He served previously as the special teams coach in Denver and Kansas City.
"If there's one thing I hope to achieve from sharing this story," Kluwe wrote, "it's to make sure that Mike Priefer never holds a coaching position again in the NFL, and ideally never coaches at any level."
The Vikings did not respond directly to allegations against Priefer in their statement, but did say they "will have further comment at the appropriate time."
Kluwe averaged 44.4 yards per punt over his career in Minnesota, including a career-high 39.7 yard net average in 2012. But he ranked just 17th in the NFL in punting that season before he was cut and he lost a competition for the punting job with the Oakland Raiders in the preseason in 2013. He had several tryouts during the season, but was never signed.
Kluwe said he wanted to wait to air his grievances until after the season so as not to provide a distraction to his friends on the team during the season.
The Vikings finished this year 5-10-1 and Frazier was fired on Monday.