As the sushi restaurant Juno opens in the Lincoln Park neighborhood for dinner, memories of last Thursday are still vivid.
This is the owner of Juno Jason Chan standing over a theft suspect. Chan found the suspect at a nearby restaurant after one of his customers had his iPhone stolen.
"I just happen to glance over to get my phone, and it wasn't there," said Gary Wolske, friend.
"I was like, 'Did that guy just take your phone?' and then Gary said, 'Oh my God, he did. I don't have my phone,'" said Jason Chan, restaurant owner.
Chan is a black belt and instructor of mixed martial arts Shidokan and he says he warned the suspect to remain until police arrived.
"He got into an aggressive stance with me, and I said, 'Don't try to hit me, if you try to hit me, I'm going to defend myself,' and then I said 'Don't even think about hitting me,'and then he tried to hit me," said Chan.
Chan says he used an arm bar hold and called police and friends while holding the suspect. Chicago Police charged Justin Ballog for misdemeanor theft.
"I think it's terrific. I think he's a shining example to being proactive," said Gary Wiviott, Barn & Company.
"While Jason was on the phone, holding this guy down, he was calmly speaking. The same way when he found out about cancer," said Eric Sawitoski, friend.
Last year, before Chan opened the restaurant, he was without health insurance. Friends started a fundraising campaign to help with his cancer treatment payments for stage four throat cancer.
So last week, Chan-- still fifty pounds underweight and recovering from chemo--harnessed his strength and training.
"To have these health issues and to be able to do this is amazing," said Wolske.
"What I did was not a hero, I wasn't a hero at all, it was being a human being. It was the right thing to do," said Chan.
Chan does not recommend this type of action for others. He says he's had many years of training and also took care to see if the suspect was armed.
Chan is cancer-free, but is not back to his full strength. He hopes would-be thieves steer clear of him and others in the neighborhood.
