January 28, 2015 4:00 AM EST

Miikka Pirinen’s photographs provoke strong reactions every time they’re seen. “People often think that these kids have been forced to fight,” the Finnish photographer tells TIME. “People think that they get hurt a lot or that their families are after the money.”

Pirinen stumbled upon these “cage-fighting children,” as they are sometimes called, when he chanced upon a video online of six-year-old kids fighting in a competition in California. “I started to follow the topic online through videos posts by these kids’ proud parents and spectators,” he says. And while he read many condemnations of the sport, Pirinen had to see for himself.

“As a journalist I was strict not to form an opinion before seeing it all,” he says. “After spending over a month, day and night, following the kids, the parents and the trainers in gyms around Arizona and California, I started to have a pretty good insight of what the sport really is about for everyone involved: Community.”

Pirinen found a community based on respect toward one another, with kids of all ages helping each other, and parents working closely with trainers to offer a safe environment for their children. “It’s not like we’re hanging out in a bar,” Clay Carpenter, the father of three young fighters from Phoenix, Ariz., told Pirinen. “Instead we come here to support our kids.”

The children pictured in Pirinen’s photographs are not bullies – in fact, most of them are among the most trusted pupils in their respective schools, the photographer says. “They look out for each other and if anyone uses their skills for the wrong reasons, they are quickly set straight.”

For Pirinen, Fight League Kids is just the latest chapter in a two-year photographic project on the issue of identity among children. “I’m interested in the different ways young people are trying to form an identity for themselves,” he says. Next, the photographer, who started his career as a camera assistant in the film industry before moving to photography, plans to continue this project, focusing instead on motor sports and American football.

Miikka Pirinen is a Finnish freelance photographer based in Helsinki. He’s a member of the Helsinki Street photography collective.

Mikko Takkunen is an Associate Photo Editor at TIME. Follow him on Twitter @photojournalism.

Olivier Laurent is the editor of TIME LightBox. Follow him on Twitter and Instagram @olivierclaurent

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