A former teacher in Texas who was captured in Syria recently explained why he left the U.S. to work for ISIS terrorists, a decision he said he doesn’t regret.

“I wanted to go see exactly what the group was about, and what they were doing,” former Sugarland, Texas teacher Warren Christopher Clark told NBC News during an interview in an undisclosed northern Syrian town.

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“Of course I saw the videos. I think with the beheadings, that’s execution,” he said. “I’m from the United States, from Texas. They like to execute people, too. So I really don’t see any difference. They might do it off camera, but it’s the same.”

The 34-year-old Muslim convert said he entered Syria from Turkey in June 2015 and spent over three years with the terrorist organization, which carried out executions and crucifixions during his tenure.

Classmates from high school told the news site Clark came from a middle class, religious family with ties to the military, but he changed when he converted to Islam around 2004. A source said he researched religion on the internet and visited radical sites, where he would watch violent YouTube videos and post anti-American propaganda.

Clark taught as a substitute teacher in Texas, then moved to Saudi Arabia, where he taught English for two years. He then moved to Turkey, before submitting his application to ISIS under the alias Abu Muhammad al-Ameriki.

“I am looking to get a position teaching English to students in the Islamic State,” the resume read. “I was born and raised in the United States and have always loved teaching others and learning from others as well. My work background is largely in English and I consider working at the University of Mosul to be a great way of continuing my career.”

The resume was recovered from a house in Iraq and later obtained by the Program on Extremism at George Washington University, which published a report on “American Jihadists in Syria and Iraq” last year.

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The program tracked the email address, education credentials and work experience listed on the resume to Clark, who alleged he never took up arms for ISIS.

“I was living in Mosul at the time, and I needed a way to support myself,” Clark told NBC News.

“I wanted to learn more about the ideology. I’m a political science major, global business minor. I like politics. I like travel, world events. That’s what I wanted to do,” he said.

Instead, he spent most of his time huddled inside of a mosque, hoping not to die.

“It was a place that was constantly being bombed,” he said. “You were always on edge. Day and night, just bombs and airstrikes. You sleep in the middle of the day. I spent most of my time living in a mosque. I just remember every day hoping not to get bombed.”

Clark’s interview with NBC News foreign correspondent Richard Engel followed his capture by Syrian Democratic Forces working to eradicate the lingering elements of ISIS in the country. He told Engel the FBI has been in contact, but he’s unsure about his fate.

The State Department acknowledged the “open source reports” but declined to comment on Clark’s situation.

The Program on Extremism’s report identifies a total of 72 Americans who have joined ISIS in Iraq and Syria since 2011.

The Houston Chronicle reports:

(Clark) will likely face criminal charges in the U.S. for supporting a terrorist group, but remains for now in the custody of Kurdish rebels fighting in Syria. If charges were brought in Houston, he would be the fourth person accused of supporting ISIS in the region. Two other men were convicted and a third has a trial pending.