Firefighter Thomas Phelan who evacuated hundreds on 9/11 dies of cancer at 45

City firefighter Thomas Phelan, an unsung hero of 9/11 who evacuated hundreds of people from Lower Manhattan while working as a ferry captain, has died.

He was 45.

Phelan died Friday of cancer. His illness was believed to be related to his exposure to the toxic fumes swirling around Ground Zero, officials and friends said.

He was working as a Statue of Liberty ferry captain when terrorists slammed two airplanes into the World Trade Center, stranding thousands of people.

Phelan turned his tour boat into a rescue vessel and played a key role in what’s been described as the largest evacuation in city history.

“He brought supplies, rescue workers & was a huge part of the operation,” according to the NYC Fire Wire Facebook page.

He went on to join the FDNY in May 2003.

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Phelan was assigned to Engine Co. 55, but was later promoted to marine patrol and transferred to Marine 9 in Staten Island.

He was credited with one save during his career, officials said.

“I’m so sad! A true hero and gentleman,” Maura Buckley wrote on Facebook.

“He would help anyone and everyone any chance he could. I just can’t believe this and honestly don’t understand why it’s always the good ones we lose way to early.”

Paul Iannizzotto wrote that he worked with Phelan at Engine 55.

“Always a stand up guy, always doing the right thing, and will be sorely missed,” he added on Facebook. “Rest easy brother.”

Edward Fahey said Phelan was a master mariner. “I was just talking to my old man and he said even at a young age you were the best boat captain he had ever seen,” Fahey wrote.

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