Editor's note: A new video featuring Islamic State leader Abu Bakr al-Baghdadi was released this week by the group’s propaganda arm al-Furqan. This is the first time the ISIS leader has been seen since July 2014. In the video, obtained by SITE Intelligence Group, Baghdadi asserts that his followers fought to the bitter end in territories and cities where they were forced out by U.S.-backed coalition forces. Baghdadi also claims that attacks on Christians in Sri Lanka on Easter Sunday were in retaliation for the defeat of ISIS in Baghouz, the group’s last stronghold in Syria.

Author Brett Velicovich, who hunted Baghdadi in Iraq while serving as an intelligence specialist in the U.S. Army. In the excerpt below from his book “Drone Warrior” he explains what it was like to try to find and capture Baghdadi.

Chapter 22: The One Who Got Away

There was always one elusive target on every tour. One guy we hunted and chased but somehow kept slipping away. Every team had its archnemesis. Mine during the summer of 2010 was a man we called Abu Dua.

We hunted Abu Dua for months, pressured sources and captives, put extra drones in the sky for eyes that never slept. Maybe it was luck. He’d probably call it divine intervention. Something Allah did for him as thanks for all the mass killings he called holy.

ISIS LEADER AL-BAGHDADI PICTURED FOR FIRST TIME SINCE 2014, INTEL GROUP SAYS

In the spring of 2010, Abu Dua was one of the most wanted men in our covert world – at the top of our target list – but he was largely unknown to the public.

Abu Dua was connected to everyone at the top of ISI and he had his own fiefdom. Among thousands of brainwashed followers, he was known as the Wali of Walis, a title usually reserved for the top three ranks in the network’s broader hierarchy. After we killed Brooklyn and Manhattan the month before, we kept hearing that he was taking over. And soon he did.

Not only did he take over the ISI network, but he would help them eventually become ISIS, morphing into an even more murderous and twisted offshoot, swallowing up parts of Syria and Iraq in 2014. He was probably the smartest terrorist I ever hunted.

Most people know him these days as the most wanted terrorist in the world: Abu Bakr al-Baghdadi, the leader of ISIS.

The U.S. government had placed a $10 million bounty on his head.

He didn’t know me, but he definitely knew my work. Through my deployment, our team conducted more than 32 raids that specifically aimed to uncover him. Most were chasing leads to his whereabouts or capturing people in his inner circle, attempts at tightening the noose around his neck. He had to see some of the closest people in his inner circle, people he met with every day, getting picked off around him. We would get word that he was running around with some target of ours during his daily terrorist duties, meeting at a gas station or some safe house somewhere, then, boom, that other guy with him was suddenly gone, in our custody or dead. Imagine everyone in your circle of friends and family that you always met the same time every week, slowly disappearing one by one over the course of a couple of months. His tight-knit group of the most brutal animals within the network slowly vanishing around him. I forced him underground and got closer to ending his reign than anyone else. But we were always just one step behind him.

There were a lot of reasons that he probably escaped our team’s grasp. He was surely better at hiding than any other man on our list. His operations security – OPSEC – was the best in the business. He was paranoid that we were getting close. He would be somewhere and then disappear without a trace, like a weather pattern. He knew, one little slip-up and we had him. No doubt our team made him the security-obsessive psychopath he was today. Paranoia kept him alive.

Usually, we got the guys we hunted. Maybe not that first tour, but eventually we got to them – and if I didn’t, another team did. My team was always followed by another team, which was followed by another, all of us hunting around the clock. But this time was different. With U.S. troops pulling out of Iraq, with fewer of our guys likely to be looking for him, I wasn’t so sure there would be another chance to get Abu Dua.

When we first started hunting him, it was because we needed a path to Manhattan and Brooklyn and we were worried that Dark Horse was dead and wouldn’t pan out. Abu Dua was one of the only other commanders who knew their whereabouts. So we hunted them both.

Abu Dua was a big fan of an ice cream shop in downtown Baghdad that had an outdoor seating area where many locals socialized all day long. Our sources told us that he met his fighters there on Thursdays and used it as a letter drop for couriers. He didn’t seem afraid of being recognized by locals at the time, only because they didn’t know about him then.

One summer day we got intelligence that he was going to the ice cream shop for a drop and we put a bird up to check it out. We watched the shop for days and days.

“What a sick joke,” Megan said as the monitors streamed back images of families eating ice cream cones. “A terrorist who loves a good ice cream sundae.” I imagined him talking to his hired killers about the next massacre over strawberry milkshakes and getting the ice cream foam on his beard.

CLICK HERE TO GET THE FOX NEWS APP

We had our local informants – the Cobras – on the street, casually mulling around and looking to snap pictures. But nothing stood out. Just families coming and going for dessert. They must have snapped thousands of photos that we sorted through back in the Box. But none of them were him. He never came. Or maybe he did and we just didn’t see him.

Pursuing Abu Dua was mostly like that.

CLICK HERE TO READ MORE FROM BRETT VELICOVICH

Excerpted from "Drone Warrior: An Elite Soldier's Inside Account of the Hunt for America's Most Dangerous Enemies" (Dey Street Books, June 27, 2017).