Steve Buscemi actually returned to his old firefighter job during 9/11 but under one condition

A day after the harrowing news first broke that two American Airlines flights had plummeted into New York's Twin Towers, actor Steve Buscemi rushed to the scene.

At the time, he was hot off the back of his latest on-screen successes, which included appearing and guest directing The Sopranos, bagging supporting roles in Con Air and Armageddon, and partnering up with the Coen brothers for Miller’s Crossing, Barton Fink, The Hudsucker Proxy, Fargo, and The Big Lebowski.

In the years prior to his acting achievements, however, the NYC-local had worked as a firefighter for four years, serving with the New York City Fire Department's Engine Company No. 55, in Little Italy, Manhattan until 1984.

He'd taken the department's civil service test when he was just 18, going on to take secret acting classes on the side.

Buscemi had worked as a firefighter for four years (Jim Spellman/WireImage)

Despite quitting the force after landing his big break with Quentin Tarantino's 1992 cult classic Reservoir Dogs, Buscemi remained in close contact with his former colleagues, attending both union rallies and reunions.

He also went on to present the HBO documentary, A Good Job: Stories of the FDNY, shedding light on the harsh realities of the profession.

For several days after the horrific September 11, 2001 attack, however, Buscemi returned to his original work, trudging through rubble and digging through dirt for over 12 hours per day in a bid to find missing victims.

Many of these individuals included fellow firefighters, who'd been first on the scene when the World Trade Centre towers first fell.

Prior to volunteering, colleagues of Buscemi claimed the Hollywood star had made one thing clear about his return to the force - he wouldn't be included in any photographs.

Buscemi spent several days at Ground Zero (Porter Gifford/Corbis via Getty Images)

The 'Brotherhood of Fire' Facebook page reminded its followers with a heartfelt post in 2013 (via The Independent): "After 9/11/2001... Brother Buscemi returned to FDNY Engine 55.

"On September 12, 2001 and for several days following Brother Steve worked 12-hour shifts alongside other firefighters digging and sifting through the rubble from the World Trade Center looking for survivors."

The post continued: "Very few photographs and no interviews exist because he declined them. He wasn’t there for the publicity."

Speaking on Marc Maron’s WTF podcast recently, Buscemi recalled the moment he first heard the gut-wrenching news of the attack.

"I was depressed, I was anxious, I couldn’t make a simple decision," the 67-year-old explained, revealing he'd gotten in touch with his old firehouse the following day, but had received no reply.

Undeterred, he headed to the site and come across his former engine company.

Buscemi recently recalled his experience as a firefighter (Maria Moratti/Getty Images)

"I asked if I could join them. I could tell they were a little suspicious at first, but I worked with them that day," Buscemi continued.

He later said of the courageous rescue attempts: "It was a privilege to be able to do it.

"It was great to connect with the firehouse I used to work with and with some of the guys I worked alongside. And it was enormously helpful for me because while I was working, I didn’t really think about it as much, feel it as much."

Despite the achievement, Buscemi went on to reveal that what he encountered at Ground Zero had left him battling PTSD for years to come.

"I was only there for like five days," he continued. "But when I stopped going and tried to just live my life again, it was really, really hard.

"There are times when I talk about 9/11 and I’m right back there. I start to get choked up and I realise, 'Ah, this is still a big part of me'."