“Great day tomorrow for a marathon. You guys going?” he said he asked the passengers, whose backpacks were nearly left in his trunk at the end of the ride. The younger man, wearing a white baseball cap ­responded, “Ah, Boston ­Marathon.”

They told him they were from Chechnya.

MALDEN — Small talk is part of Jim Duggan’s job as a taxi driver and he considers himself a natural at it, so after several minutes of silence while he drove two backpack-toting young men from the MBTA station here to Cambridge on the morning of April 14, he decided to engage them in light conversation.


Suddenly, the older customer, wearing a black baseball cap, cut the younger one off, yelling angrily at him in a foreign language, his outburst startling Duggan.

Duggan said he has ­described the encounter to two US Department of Homeland Security agents who showed up at his house last weekend, telling them how those customers told him to stop abruptly just several blocks from their stated destination, Norfolk Street, ­after his attempt at small talk and how he almost drove away with two heavy backpacks the men had placed in his trunk.

Duggan said he contacted the FBI last Friday after he realized that he may have provided transportation for Tamerlan Tsarnaev, 26, and Dzhokhar Tsarnaev, 19, who allegedly planted the lethal bombs that exploded on Marathon Day. They lived on Norfolk Street in Cambridge and allegedly carried the two bombs they detonated in backpacks.

After calling the FBI, said ­Duggan, he received a call from the Homeland Security agents, who interviewed him for nearly an hour in his backyard in Malden.

Duggan said he called Malden police after talking with the federal authorities.

Malden Police Chief Kevin Molis confirmed Thursday that Duggan contacted his department and said a Malden detective who is part of a joint FBI task force spoke with Duggan and forwarded his report to the FBI.


“I can’t speak about the ­nature of the investigation ­because federal authorities are completely handling it,” Molis said.

The Department of Homeland Security and FBI did not respond to requests for comment Thursday.

Duggan says he is certain that the two men he picked up are the same ones he viewed in the FBI’s widely circulated surveillance video of the suspects, which he did not see for several days. On Thursday, he grew emotional when he spoke of how they screamed and banged on the side of his taxi as he started driving away before they had removed their backpacks from the trunk.

“They certainly wanted to get my attention, because they slammed their hands repeatedly on the back: Bang, bang, bang!” he said.

Duggan said he realized he had forgotten about the bags, so he stopped, popped his trunk and got out.

“They were angry at me, so I tell them, ‘Excuse me, I’m a ­human being. I made a mistake, and I’m sorry.’ ”

Duggan said that when he opened the trunk and lifted the dark backpack the older man had carried, he was shocked by its weight.

“It was as full as it could be, and it was very heavy, so heavy that I had to brace myself and try to lift it again,” said Duggan, estimating that the bag weighed more than 20 pounds but less than 50.


The older man started screaming again and snatched the backpack from Duggan.

“I told him to relax, that I was just trying to help,” Duggan said.

Duggan said he remarked to the older customer, “You know what, that is the most packed backpack I’ve ever picked up. I don’t know what you got in there, but, hey, have a nice day.”

The interaction with those customers remained on ­Duggan’s mind for several days.

“I kept remembering that kid in the white polo cap. During the ride I asked him where he got the cap, and he said the Wrentham Mall.”

Duggan said he woke up last Friday at 2:30 a.m. for work. He had fallen asleep with the television on, and as he sat up and stretched on his bed, he saw a news account about the suspects. He heard the reporter mention Norfolk Street.

“And that’s when I knew,” Duggan said.

Brian Ballou can be reached at bballou@globe.com. Follow him on Twitter @GlobeBallou.