A Warren County doctor who responded to Ground Zero 20 years ago said the efforts to find survivors among the wreckage of the World Trade Center have helped shape his career in emergency rooms ever since.

On September 11, 2001, Dr. Randy Mariott got the call to make the trip to New York City as part of Ohio Task Force 1.

“We thought that we were heading there with significant potential of being able to rescue live victims,” he said. “That was our hope.”

For the medical director of Premier Health EMS Center of Excellence, that hope never materialized. When they got to New York City on Sept. 12, there were no survivors to find. The team instead focused on recovering remains, and Marriott attended to the health and safety of other first responders.

“That was the most difficult part,” he said. “The realization that nearly 3,000 of our fellow citizens, not to mention over 400 first responders, were still in that pile and we probably could do nothing to help them.”

His time at Ground Zero has often influenced his work as an emergency department doctor at Premier Health’s different hospitals across the area, he said.

“I think that just the preparation has played a role in my career,” Marriott said. “I’ve tried to focus on doing more with less.”

In addition to having the experience influence his career, he also said the terrorist attacks may have helped make a doctor out of his son.

“I picked him up at his middle school on the way to the hospital to get medical gear that we had to take with us,” Marriott said. “He actually helped me carry out the medical supplies that went to Ground Zero.”

Warning: The following content may be distressing for some viewers.

Hundreds of New York firefighters and police officers immediately headed to work once Flight 175 hit the South Tower. One of those officers was Louis Savelli.

After leading the NYPD counter-terrorism unit created in the aftermath of the attack for many years, the born-and-bred New Yorker eventually moved his family to Iowa for a fresh start, opening an authentic pizzeria in 2014. He brought a little piece of the Big Apple with him: posters, pizza ovens and his prized accent.

The retired detective came to Camp Dodge with lessons learned from 9/11 to teach counter-terrorist training to law enforcement all over the country.

"That was my unit... to arrest members of Al-Qaeda," Savelli said.

"When the second plane hit, which I knew right away, and then everybody knew right away that was a terrorist attack. I ran right into work," Savelli said.

It was a life-changing day burned into his mind.

"The streets of New York were mayhem," Savelli said. "People were trying to drive all over to get places. Nobody was stopping at lights. Horns were beeping. It was something out of a movie, like a science fiction movie."

Savelli shared photos that he had captured from ground zero.

"It was just constant dust for quite a while, from all the debris, from the pulverization of the buildings, all the stuff that was in the air. It was very surreal," Savelli said.

He and his team worked frantically.

"Trying to sift through tons and tons of rubble by hand, trying to find people. And then just being frustrated not really finding anything," Savelli said.

However, there were only a few survivors.

"A lot of memories of specific things... are kind of, like, blurry or nonexistent," Savelli said. "So a lot of things that happened, it's hard to remember specific things. But I do remember my recovery efforts at ground zero were mostly body parts. It's kind of hard to say on TV. I don't remember an entire person, finding an entire person on that day, on 9/11, and then throughout that time. I assume that ... not remembering is a part of my mind blocking it out."

Now, 20 years later, he cannot block it out. Like many of the first responders, Savelli is suffering. The dust he breathed in at ground zero has caused asthma, skin cancer and gut-wrenching stomach pain now.

"Sadly, all those guys that stayed there looking for people and looking for DNA, and anybody who could've at least recovered something for the family, every one of them has gotten seriously sick," Savelli said. "At least 5,000 total first responders have died of cancer. And about 15,000, 20,000 have gotten some sort of serious cancer-related disease since then."

In addition to the pain is the fear that terrorism will rear its ugly head on United States soil again after pulling out of Afghanistan.

"Without a doubt, we are much more at risk today than we've been in a long time," Savelli said. "Are we going to have people like Taliban or ISIS or Al-Qaeda or Haqqani Network or some others coming in with them? And without a doubt that will happen. So we have to do a better job."

Aside from his pizza businesses in Des Moines, Savelli also runs a security firm.

"I was a member of the NYPD on 9/11 at ground zero and you know we did our job, but the United States military sacrificed so much to go overseas and protect this country," Savelli said. "And they are my heroes."

He said we should remember that the people willing to put their lives on the line, don't do it for the money.

"The people out there sacrifice, for very little money. The cops, the firefighters, the military, EMTs, they make very little money," Savelli said. "But yet they risk their lives out there for strangers."

Warning: The above video has footage that may be upsetting to some viewers.

Sept. 11, 2001, was a sunny day in New York City.

Randal Robinson, of Savannah, Georgia, had just arrived for a morning U.S. Customs Service seminar, being held on the fourth floor of Six World Trade Center.

One of the buildings that would soon be gone.

"And then when the thing hit...Boom. One of the New Yorkers said, 'Oh we don't have earthquakes in New York very often.'

And then.... Boom boom rumble rumble.... Dragging scraping sound.

Oh... somebody's moving furniture.

And we thought.... 'Naah.'

Then somebody stuck their head in the door and shouted, 'Everybody out....now! Do not go down the elevator. Come down the steps and follow me.'"

Robinson remembers it all like it was yesterday. How they all dashed down the stairs to the street below. He looked up and saw the smoke.

Somebody said a corporate jet must have struck the building. He couldn't figure out how the pilot could have done it.

"Well heck, it had to be a heart attack or a stroke," he said. "It was beautiful weather. You couldn't miss seeing it. So I said, 'Well, hopefully, they'll get the fire put out soon.' So I pulled out my camera and started taking the pictures."

He snapped about a dozen images before realizing just what he was witnessing.

"So then when I ran out of film," he said, "I put in another roll of film and started to take more pictures and then someone said, 'Oh my gosh, people are jumping out.' So I said no more pictures."

He thought the firefighters would put it out. But they had no chance.

"In a few minutes, someone said 'Oh my god, here comes another one.' This other jetliner was coming down the river. Banked hard left. Came over our heads, engines screaming and hit Two World Trade Center."

He finally made it back to his hotel room and watched on TV with the other guests as the towers fell, including the building he had evacuated.

"...Thank the Lord we all got out safely."