Police arrested a man who they said used a fake badge, and in one case, a box of dirty magazines to commit a series of robberies in Seattle parks.

Police have been searching for 46-year-old Ryan James Purdy since December, and finally caught up with him Wednesday after he bragged to a bus passenger about his life on the run, authorities said.

Investigators said Purdy was riding a bus in Auburn Wednesday when he began talking to a fellow passenger and mentioned he was wanted by police for impersonating an officer.

The passenger, Raymond Martin, recognized Purdy from a picture in a kirotv.com story about the robberies that he had read on his phone.

"When he started talking to me, everything started clicking," Martin told KIRO 7 Eyewitness News reporter Amy Clancy.

"He was telling me that he was robbing people," Martin said, "acting like he was a cop, and taking their wallets and taking their credit cards."

"When he started talking to me," Martin said, "I was like, 'I read about you on my phone! A matter of fact, your picture's on my phone, let me show you.' And then I showed it to him and he was like, 'Boy, I got to get out of here.'"

Purdy immediately boarded a different bus, and Martin called the police.

"I got on the phone, I called 911, I'm like, 'Hey, I've just seen the guy you're looking for that was doing the cop impersonation," said Martin. "'He's on the 181 (bus) heading to Auburn.' I told them what he was wearing."

When Auburn police officers arrived, Purdy gave them a false name in an attempt to convince them he was someone else, police said.

He was booked into the Auburn Jail.

Police say Purdy would approach his victims at Seattle parks, flash a badge and then ask to see a wallet to check identification.

Purdy would flip through the wallet, hand it back and tell the victim he was part of an undercover sting.

The victims later discovered they were missing bank or credit cards.

Martin told Clancy that he believes that Purdy was arrested just in time. While waiting for and riding the bus together, he said Purdy talked about getting some money and then driving to Texas, because "the heat was just getting too hot."

As for Martin, he said that he had to do what was right. "I felt good," he said.