Substitute math teacher Ryan Fish faces charges including reckless endangerment and risk of injury to a minor after running an underground "fight club" in a Connecticut high school.

Connecticut substitute math teacher Ryan Fish, 23, was arrested after video of him encouraging students to engage in physical brawls was discovered. Fish is now being accused of supervising a teenage "fight club."

Fish has pleaded not guilty to charges including reckless endangerment and risk of injury to a minor after he was seen in cell phone video amidst his Montville High School students fighting each other, according to The Associated Press. The teacher claims that his students were just being "rambunctious" and that he had nothing to do with starting the melee.

Fish was fired by the school in October, after Assistant Principal Tatiana Patten learned about the fights and informed Principal Jeffrey Theodoss, according to The Day, a New London-based newspaper. Official police investigations into the situation began in December after a student told a social worker he had been physically assaulted at the school. Patten then spoke to police about the "fight club" that had been discovered in Fish's classroom. School officials say they learned of even more videos of fights in December.

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In January, Patten was placed on leave pertaining to separate investigations done by police and the school district, according to The Day. It is unclear if that investigation is connected to Fish's arrest.

Gary Kleeblatt, spokesman for the state Department of Children and Families, expressed concern for the students at the school.

"Legitimate sports activities involving boxing with correct equipment and safety gear" would be entirely OK, he stated to The Day, but Fish's bare-fisted math class brawls "would definitely be of significant concern to us."

Due to privacy issues pertaining to the investigation, many of the details of the videos remain vague. Superintendent Brian Levesque has said that he cannot comment on the videos, which were discovered on the district's servers.

"As soon as we learned of his involvement in this, we immediately terminated his employment," Levesque said in a statement. "Student safety is our highest priority each and every day. We believe our staff does a great job of protecting the safety of our students each and every day. This situation was very unfortunate, but not indicative of our regular operations."

Police have identified four victims ranging from ages 14 to 16, according to The Day. At least two separate fights occurring on two different days have been caught on video. Police say one victim had described Fish as a mentor.

In the footage, Fish can be seen encouraging the battles. In one video, a student stopped fighting after he began throwing up. Fish attempted to get him to go for round two when he stopped vomiting.

"I just try to be the teacher that the kids could come to and actually express themselves and actually work through their issues," Fish told police, according to BuzzFeed. "The truth is I'm an idiot and wanted to be friend [sic] them. [...] I'm immature."

[Photo: Connecticut State Police]