Ultimate Fighting Championship fighter Matt Mitrione has been suspended indefinitely after calling Fallon Fox, a transgender female MMA fighter, a “lying sick sociopathic disgusting freak” in an interview with “MMA Hour” on Monday. UFC and Zuffa LLC issued a statement announcing Mitrione’s immediate suspension and investigation into the comments.

Mitrione was being interviewed by Ariel Helwani on Monday’s “The MMA Hour.” Mitrione, a former NFL player, fights as a heavyweight in the UFC with a record of 6-2 with his last fight being a knockout victory against Phil De Fries at “UFC On Fuel TV: Mousasi vs. Latifi” in Stockholm, Sweden.

Helwani’s interview with Mitrione began with the two discussing Mittrione’s Europe vacation with his training partners and his recent win. Mitrione also discussed nearly being arrested in Sweden in a case of mistaken identity before discussing Fox. Toward the end of the interview, around the 17-minute mark, Mitrione segued into discussing Fox with a reference to “The Silence of the Lambs.” Mitrione said, “Instead of being called the Queen of Swords, she should be called Queen of the Buffalos,” a reference to Buffalo Bill, the main villain in the film.

Mitrione made a few more jokes about Fox, referring to her as "him," when Helwani asked Mitrione to explain the attacks on Fox. Mittrione said, “He's chromosomally a man. He had a gender change, not a sex change. He's still a man. He was a man for 31 years. Thirty-one years. That's a couple years younger than I am. He's a man. Six years of taking performance de-hancing drugs you think is going to change all that? That's ridiculous. That is a lying, sick, sociopathic, disgusting freak.”

The UFC quickly issued a statement saying, “The UFC was appalled by the transphobic comments made by heavyweight Matt Mitrione today in an interview on the 'MMA Hour.'” The statement continued, “The organization finds Mr. Mitrione’s comments offensive and wholly unacceptable and -- as a direct result of this significant breach of the UFC’s code of conduct -- Mr. Mitrione’s UFC contract has been suspended and the incident is being investigated.”

Fox, 37, is a controversial figure in MMA as its first transgender fighter. Fox was born a man but underwent gender reassignment surgery after college. In an interview with Sports Illustrated, Fox described her struggles with gender identity but did not discover the term “transgender” until she was 17 years old and when she was 19 she got her girlfriend pregnant.

Fox joined the Navy to support her family, married her girlfriend and, after being discharged, went to the University of Toledo and worked as a truck driver to pay for gender reassignment surgery.

During college, Fox told SI her struggles with gender began affecting her physically and she decided to undergo surgery. "My hair was falling out, which wasn't good for my psyche, and I knew I couldn't wait, because the longer you spend not transitioning the more the effects of aging make the transition not so pleasant,” Fox said.

Fox had to tell her four-year-old daughter that she was going to undergo surgery to become a woman, and she said her daughter took it well. After saving enough money working as a trucker for four years, Fox went to Thailand in 2006 to undergo surgery where she had a breast augmentation, gender reassignment and hair transplant surgery at the Bangkok Natural Hospital.

Five years later, in 2011, Fox began competing in MMA as a female athlete and would later have facial surgery to reduce the prominence of her brow and jaw line, SI reports. Fox is currently 1-0 in her professional bouts, 3-0 as an amateur, and has the support of her 16-year-old daughter as she competes as a female MMA fighter.

Fox’s transgender status has led to many debates about whether or not she should be fighting with females. Some argue the science of it, claiming hormonal or biological advantages to being a born a man, while other experts dispute the possible advantages. UFC fighter Meisha Tate said in an interview with ESPN she would not take a bout against Fox citing fighter safety.

You can view Mitrione's interview below.