Mike Thomas knew the dog didn't belong to the man who brought him onto the bus.

PORTLAND, Ore. — TriMet bus driver Mike Thomas knew something was up when he first saw Cooper, a 4-year-old yellow lab, walking down the middle of Capitol Highway with an unknown man. The man was only holding onto Cooper by the collar.

"You don't expect to see a person in the road. Let alone a person with a dog," Thomas said.

Thomas stopped the bus and, out of safety concerns, let both get on board. Except, the man let go of Cooper's collar and didn't bring him on the bus at first.

"I asked him, 'Is that your dog?'" Thomas asked the man. "He said, 'Yes, but he's OK.' I said, 'No you need to get your dog, he's in the road.' So he called. He said 'come here,' but he didn't say the dog's name. The dog came back and he pulled the dog on by the collar."

That interaction also struck Thomas as odd. At that point he knew something was up. While the man was sitting on the bus, he began chatting up another passenger. Thomas said he overheard him offer her the dog.

About an hour went by with both sitting near the front of the bus. When it came time for the man to get off, that's when Thomas stepped in.

"I grabbed Cooper's collar and said the dog's gonna stay with me. I would be getting him back to his family."

That family is Jane Murphy of Southwest Portland. She was in Hawaii on vacation. Her dog was being cared for by her son. He works for the Trail Blazers and was at the game that night. Both have no idea how Cooper escaped or was stolen. They're just glad he's home, all thanks to the awareness of TriMet bus driver, Mike Thomas.