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It was the day before the Boston Marathon, and Jim Duggan's morning was off to a slow start. He was the only cab hanging around a train station, and was about to pull away and grab a cup coffee, when he spotted two guys in his rear view mirror. One of them wore a white baseball cap, his curly hair sticking out. The other wore a black cap.
"On my mother's soul, those kids were in my cab," said Duggan. "Those kids" would be Tamerlan and Dzhokhar Tsarnaev, the Boston Marathon bombing suspects.
Duggan got out, and the two men asked to be taken to Cambridge, a city just north of Boston. Duggan said no problem.
"They had two backpacks. I reached out to help them put them in the trunk, and they wanted to put them in themselves," said Duggan.
The two men were adamant about handling those backpacks themselves.
During the ride, Duggan and his passengers talked about a lot of different things. The Boston cab driver asked them if they were from Saudi Arabia. They said they were from Chechnya.
As the cab approached its destination, Duggan pointed to an area over the bridge, and told them that the Boston Marathon would be held there the next day. If they hadn't seen it, said the friendly cabbie, it might be a good experience.
"And the little brother said, 'Oh, Boston Marathon?'," said Duggin. "And then the older brother got real aggressive."
The younger passenger began reassuring Duggan, telling him the fight was just between him and his brother. He told Duggan to pull over.
The two men paid the fare, and got out of the cab. Duggan, without thinking, put the car in drive and started to pull away. The men immediately started screaming, and banging on the trunk of Duggan's cab.
"I get out, and they were angry," said Duggan. The cab driver held his hands up in apology, exclaiming, "Sorry, I forgot! It was a mistake, people make mistakes."
Duggan popped the trunk, and the younger brother reached in and grabbed his bag. The cab driver reached in to get the other bag.
"It was heavier than it should have been," Duggan said.
Days later, when the FBI released the first grainy images of the Boston Marathon bombing suspects, Duggan recognized that white cap, with that curly hair sticking out. He called the FBI shortly after, and told him his story.
"The thought that I had that kind of evil in my car," said Duggan, "the thought that I picked up what could have been that bag, is terrifying."
Sources confirm to CNN that DHS officials met and interviewed Duggan, and are taking his story seriously.