YONKERS, N.Y. (CBS 2) — In Yonkers, firefighters rescued two men dangling off a collapsed scaffolding. It was still not known Saturday what went wrong to cause the scaffold to collapse.

Chopper 2HD was there each step of the way in the nail-biter of a rescue on the side of one of the tallest buildings in Yonkers for seniors at 289 Nepperhan Avenue.

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Two men were apparently working on the facade on around the 13th or 14th floor when their scaffolding gave way.

Dennis Richmond was at a nearby bus stop when he heard a thud, then one of the men screaming. “I called the police because I saw the two men falling down. One of them was actually standing on top of the scaffolding. The other was hanging on for his life,” he said.

“I see this out of the window. I’m like ‘Oh my God. This is crazy,” another witness said.

A fire engine ladder was fully extended, but it just wasn’t enough. “The ladder came up about a floor and a half so they were out of reach,” said Asst. Fire Chief Roger Vitolo.

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The two dangling workers on the twelfth floor were in safety harnesses, but no one knew for how long the harnesses would hold them in place.

“They were reaching a panic point and were both getting hypothermic and there’s also a thing called harness compression syndrome. If they stay in those harnesses too long, it could become a life-threating situation,” said Fire Chief John Flynn.

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Addtional safety line were extended to the men from the window as a precaution, while the hero of the day was descending from 14 stories above, from the roof.

Rope rescue expert Mike Giroux was a hero not once, but twice. The 10-year veteran firefighter secured the first worker to a line then rappelled with him to the street where he was taken off in an ambulance.

“It makes you feel great. It makes you say that all the training you do is worth every bit of it,” Giroux said. “I like this stuff. This is, this is what I thrive on.”

The second worker was rescued the same way, but first had to be freed from the remnants of the scaffold and the various ropes and belts.

It was tricky and time consuming, and the crowd cheered when all went right.

“Basically you look down and make sure you have a clear way to go down there, that you’re not going to get tangled up, your ropes are not going to get tangled up,” Giroux said.

“We kept reassuring them every minute that they were going to be alright,” Yonkers police officer Jaime Molina said.

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“You don’t see stuff like this every day,” one witness said.