Watch this hero stop a crazy man from stealing a baby in New York's Madison Square Park:

33-year-old Brian Kemsley is a Muay Thai coach and has over a decade of jiu-jitsu training. Originally from Hong Kong, Kemsley is both a martial arts champion and a hardcore punk rocker with the bands Grave Maker and Outbreak.

When Kemsley and his girlfriend saw a man trying to pull a baby out of a woman's stroller, he sprang into action.

"I was trying to get him away from the mother, and let her get away to safety," said Kemsley.

He also noted that the crowd of people around him wanted to pound the would-be kidnapper, saying he had to "keep the guy safe from the mob" before police arrived.

It seems the criminal was literally crazy, as Kemsley indicated the man thought he was talking to Obama in the Oval Office. The man also shouted, "How do you know this isn't my baby?" and "This could be my baby, you don't know that!"

After taking him to the ground and pinning the man with his arms and legs, Kemlsey had to hold onto the attacker for over 15 minutes before police finally got to the scene. The crowd even tried to flag down an NYPD van to no avail (thanks for those budget cuts, Mayor De Blasio!). The police then reportedly took the attacker to a hospital for mental evaluation.

One thing's for sure: this might not have been karate, but Mr. Miyagi still approves.