In this photo taken by the NYPD and provided by...

In this photo taken by the NYPD and provided by ABC News, smoke and ash engulf lower Manhattan after terrorists crashed airplanes into the World Trade Center. (Sept. 11, 2001) Credit: NYPD

NYPD Det. Gregory Semendinger, flying the first helicopter above the Twin Towers on Sept. 11, 2001, scoured the rooftops through angry black clouds of smoke, hoping to see someone, anyone.

But no one had made it to the roof to be rescued, he recalled Wednesday.

"We didn't find one single person. It was surreal," he said.

Flying closer, he didn't realize the second plane was about to strike, nor that the nation was in the midst of a terror attack.

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Without anyone to rescue, Semendinger began to shoot photos of the scene.

"There was no sound. No sound whatsoever, but the noise of the radio and the helicopter. I just kept taking pictures."

Wednesday some of Semendinger's photos were released by ABC News, which obtained them under the Freedom of Information Act. The photos had been in the custody of the National Institute of Standards and Technology, the agency that investigated the towers' collapse.

On sky patrol

A member of the NYPD aviation unit based out of Floyd Bennett Field in Brooklyn, Semendinger was co-pilot on a police Jet Ranger helicopter that for three hours - stopping only for refueling - patrolled the sky at the Trade Center site. Armed with two still-photo cameras, Semendinger took hundreds of color photographs of the devastated area and captured haunting images of the North Tower collapsing in a shower of debris and pulverized human bodies.

"I almost didn't realize what I was seeing that day," Semendinger said. "Looking at it now, it's amazing I took those pictures. The images are . . . stunning."

In an interview with Newsday Wednesday, Semendinger, 60, who retired from the NYPD in 2002 and lives in Wantagh, described how at first he and pilot James Ciccone thought they could rescue people from the roof of the burning building. In fact, Semendinger said he had rescued a woman from the tower in 1993 after the first terrorist bombing.

Semendinger said he and Ciccone functioned as an aerial observation post, describing to the Federal Aviation Administration and NYPD commanders on the ground what they saw. But flying in a pattern north of the tower, Semendinger said they were unaware of the second aircraft approaching the South Tower, narrowly missing another NYPD helicopter. It was only after the fireball exploded out of the side of that building that Semendinger and Ciccone realized the nation was under attack.

"We knew it was a terrorist attack, we knew," he said.


Frozen in time

Semendinger said he shot more than 245 digital images and three rolls of still film. But the most dramatic were a series of shots posted on the Internet Wednesday by ABC of the North Tower collapsing. Frozen in time, the cascading building and billowing debris give the impression of a gray geyser. Other images captured the clouds of debris enveloping buildings, vehicles and people in lower Manhattan.

Jan Ramirez, chief curator of the National September 11 Memorial and Museum, said of the images: "It was incredible reporting." Semendinger's photos of the collapse captured the "apocalyptic plume" of debris and its "angry coloration," Ramirez said.

"Everything was pulverized as it went down, pulverized, just amazing the forces that were at work when these things went down," said Semendinger of the towers.

While he saw people in the tower before it collapsed, Semendinger said he didn't consider their fate at the time because he was so focused on doing his job and talking to police on the ground. He didn't learn until later that some of what he saw falling from the buildings were people.

A spokesman for the NYPD Wednesday wasn't aware of the images obtained by ABC and declined to comment.

Sally Regenhard, whose firefighter son Christian died in the attack, said she was gratified by the release of the photos. "I am glad to see those pictures, even though it wrenches my heart," she said. Regenhard called for all Sept. 11 materials in the hands of the government to be released.

With Mario Gonzalez and The Associated Press

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