Abu Bakr al-Baghdadi. Screenshot/http://www.pbs.org/wgbh/pages/frontline/rise-of-isis/ Very little is known about the Islamic State leader who is often compared to Osama bin Laden and has been called "the world's most dangerous man."

But an interview with a jihadist who was reportedly jailed with Abu Bakr al-Baghdadi a decade ago sheds more light on the mysterious figure and how the Islamic State was born from a US-run prison in southern Iraq. Martin Chulov wrote an in-depth article for The Guardian that explores how al-Baghdadi and others used Camp Bucca as a planning ground for terrorism.

Abu Ahmed, who is now reportedly a senior official within the Islamic State (aka IS, ISIS, ISIL, or Daesh), said he was taken to Camp Bucca in summer 2004. He told The Guardian that he had feared the prison before he arrived.

"But when I got there," he said, "it was much better than I thought. In every way."

Camp Bucca has previously been credited with providing the perfect environment for a terrorist group to form, but Ahmed's comments describe in more detail just how integral the prison was in allowing jihadists to organize.

Bucca held jihadists from all corners of Iraq, and it seems they were all given enough freedom within the prison to collude with one another.

"We could never have all got together like this in Baghdad, or anywhere else," Ahmed told The Guardian. "It would have been impossibly dangerous. Here, we were not only safe, but we were only a few hundred meters away from the entire Al Qaeda leadership."

Ahmed quickly realized that others in Camp Bucca deferred to al-Baghdadi.

A reported picture of al-Baghdadi. Iraq Interior Ministry | Getty Images Al-Baghdadi was detained by US forces in Fallujah in 2004 during the insurgency against US forces in Iraq. He was eventually taken to Camp Bucca.

The Americans who ran Camp Bucca apparently respected al-Baghdadi, according to Ahmed and other prison sources The Guardian spoke to.

"He was respected very much by the US Army," Ahmed told The Guardian. "If he wanted to visit people in another camp [within Bucca] he could, but we couldn’t."

Americans at Bucca reportedly saw al-Baghdadi as a "fixer" who could help keep peace at the prison. But other prisoners realized that he was chasing status and seeking out a position of power.

While al-Baghdadi was charming his captors, prisoners within Camp Bucca were formulating ideas that would eventually become the worldview of the Islamic State.

"If there was no American prison in Iraq, there would be no IS now," Ahmed said. "Bucca was a factory. It made us all. It built our ideology."

Over the past year, ISIS has risen from the vacuum created by the Syrian civil war to become may be one of the most heavily armed and well-funded terrorist organizations of all time. Since August, a US-led coalition against ISIS has launched more than 660 airstrikes against ISIS in Iraq and Syria.

A look at US-led airstrikes as of Oct. 19. REUTERS

In December 2004, when the US determined that al-Baghdadi was no longer a threat and authorized his release from Camp Bucca, he rose to power in Iraq. Many others released from American prisons in the country also went on to join ISIS.

"We had so much time to sit and plan," Ahmed said. "It was the perfect environment. We all agreed to get together when we got out. The way to reconnect was easy. We wrote each other's details on the elastic of our boxer shorts. When we got out, we called."

He continued: "By 2009, many of us were back doing what we did before we were caught. But this time we were doing it better."

US officials have wondered whether Camp Bucca helped further radicalize al-Baghdadi and turn him into the ruthless leader he is today. One former Air Force officer who was a commander at Camp Bucca noted in July, when al-Baghdadi declared himself the "caliph" of ISIS, that many at the prison wondered whether they had created a "pressure cooker" for extremism.

Once released from Camp Bucca, al-Baghdadi rose through the ranks of ISIS to become a trusted aide to the then-leader of the group, Abu Omar al-Baghdadi, according to The Guardian.

In 2010, Abu Omar was killed in a raid led by US forces. At the time, Abu Bakr was one of only three people responsible for carrying important messages in and out of Abu Omar's hideout.

Abu Bakr "became the closest aide" to Abu Omar, Ahmed told The Guardian. "The messages that got to Osama bin Laden were sometimes drafted by him and their journey always started with him. When Abu Omar was killed, Abu Bakr was made leader. That time we all had in Bucca became very important again."

Here's how Islamic State's leadership structure looks right now: