Boston man Jean-Paul LaPierre, who caught a Blue Line train Sunday morning to the Chicago Marathon, said he didn’t hesitate to act when he heard someone was robbing people on the train.

“I don’t like people that strike fear in people like that,” he said. “I don’t like bullies.”

A man boarded the train about 5:50 a.m. and showed a handgun to passengers while demanding their money in the 5800 block of North Cumberland Avenue, Chicago police said.

“He was very quietly robbing people,” LaPierre said. “I went up front and said to him, give me the gun and we started fighting for the gun.”

A Good Samaritan disarms a man who was robbing CTA riders on their way to the #ChicagoMarathon. See the video and hear from the hero on @WGNNews at 4 & 6pm. pic.twitter.com/v3IWRQiRop — Ben Bradley (@BenBradleyTV) October 15, 2019

With all of the adrenaline in his system, LaPierre said he wasn’t thinking about getting shot when he approached the armed robber. “Once I got a few feet from him I knew he wasn’t going to be able to react fast enough to shoot me.”

“I was going nuts,” he said. “When I see someone pull a gun it makes me angry, it makes me really, really angry.”

LaPierre said he managed to pry the gun away from the man and was holding onto it with his right hand while maintaining a firm grip on the robber with his left.

“The man in front of me said he could put the safety on, so I handed him the gun and he put the safety on and walked it out of the train,” LaPierre said. “At this point, I was alone on the train with this guy and I had no more weapon,” LaPierre said.

“I kept telling him if you move I’m going to knock you out. I’m going to hit you seven times in three seconds.”

After that, the man “calmed down and waited for the police,” LaPierre said.

Officers told the man to get on his stomach, but when he instead laid on his back, LaPierre ran to him and “flipped him over like a hamburger and then they cuffed him” LaPierre said.

Tremaine Anderson, 30, was arrested and charged with unauthorized use of a weapon, police said.

LaPierre, who said he was in town to run the marathon, said this isn’t the first time he’s stepped into the role of Good Samaritan. He said he helped rescue a boy from a vehicle crash in Boston a few years ago, and tracked down a missing python in Newton, Massachusetts.

“I’ve been involved in a lot of things,” LaPierre said. “I just seem to be at the right place at the right time, is what people tell me.”