Here's what firefighter Gary Martin did on his vacation to Chicago: He chased down a purse-snatcher who robbed an elderly woman on North Michigan Avenue and pinned him to the ground.



"I grabbed him by the scruff of the neck,'' said Gary Martin, 47, from London, Ontario. "He went down right away. He really didn't have a whole bunch of fight in him. It wasn't like an all-out brawl."



In town for the first time, Martin said he wanted to see what he'd look like sporting a Cubs cap so he popped into a Michigan Avenue shop around noon Tuesday with his girlfriend.



"I had it on and I was looking in the mirror in this little gift shop and I just heard a woman kind of behind the store screaming, 'My purse, my purse,' '' Martin said Thursday.



He checked the building lobby and saw a man running for the revolving doors. He "put two and two together'' and went after him, he said. "It was kind of weird. He was in the one (door space) right in front of me."



Martin, still wearing the Cubs hat with its price tag dangling, said he never lost sight of the mugger through the crowds on Michigan Avenue toward Wacker Drive.



"I didn't want him to get away,'' Martin said. "I just thought it's what I should do."



Martin said he finally caught the man as he tried to run down a stairwell.



Martin, at 5-foot-10 and 185 pounds, said the man was a lot taller than him but thinner. "I had him pinned to the ground,'' Martin said. "I think he thought he was going to get a beating.''



It wasn't long before the building security officer raced up and helped him drag the man back to the building. Police arrived "very quickly'' and arrested the man, Martin said.



The woman left after thanking him, but police were able to find her after checking with her doctor's office.



Gregory Froggs, 49, of the 3500 block of South Rhodes Avenue, was charged with felony robbery, according to police. He is being held on $250,000 bail.



Martin said the incident "doesn't taint my view of Chicago at all. Chicago is a beautiful city. I know that happens in every big city. The only thing I'm ticked off about is the Blackhawks beat my Bruins."



rsobol@ tribune.com

Twitter:@RosemarySobol1