Jihadists' Computers '80 Percent' Full of Porn, Ex-Official Says Retired Lt. Gen. Michael Flynn says extremists not only “sick” but hypocritical.

 -- Computers belonging to Islamic extremists and recovered by coalition troops are often chock-full of pornography, according to a former top U.S. intelligence official.

In his new book, retired Lt. Gen. Michael Flynn, a former head of the Defense Intelligence Agency, writes that extremists in al-Qaeda and specifically the al-Qaeda branch in Iraq that became ISIS were "sick, psychopathic foes."

“We were facing a despicable foe, one who would rape and pillage women and children, boys and girls, behead for fun, all while watching pornography on their laptops,” Flynn writes, after describing U.S. efforts in Iraq in the mid-2000s. “In fact, at one point, we determined that 80 percent of the material on the laptops we were capturing was pornography.”

A current counterterrorism official, a former intelligence analyst and ex-soldiers told ABC News that while they couldn’t speak to the 80 percent figure, in their experience, pornography was often found on jihadists' computers.

“Some of it was really bad, and it was all over the map. Some of it was kids, animals,” said the former analyst.

Two former special operations soldiers, who separately went on countless raids against terror targets in Iraq, said they personally found pornography on many of their missions -- both on laptops and in the form of magazines and DVDs.

"Those guys had all kinds of sick s---," said Jack Murphy, an ex-Special Forces soldier and current editor-in-chief at the special operations news website SOFREP.com.

In one infamous case, a huge stash of pornography was found by U.S. Navy SEALs during the raid that killed Osama bin Laden in Abbottabad, Pakistan, in May 2011, according to a U.S. official. The official said at the time that the material was hidden away in a wooden box in the al-Qaeda leader’s bedroom.

A former counterterrorism official told ABC News that U.S. intelligence initially suspected coded messages might be hidden in the bin Laden porn files, but it turned out they were just what they appeared to be.

The viewing of pornography is generally seen as “haram,” or forbidden, in mainstream Islam, not to mention in the extremist interpretations espoused by al-Qaeda and ISIS.

But a senior law enforcement official who has worked terrorism cases involving al-Qaeda and ISIS in the U.S. and abroad said, “There has yet to be a case where some crazy porn stuff hasn't come up ... It never fails.”

The former analyst said that it’s possible the terrorist groups’ strict public posturing fueled perverse private habits like the viewing of extreme pornography and, in the more recent case of ISIS, codified sexual abuse of female slaves.

“I think it’s indicative of their hypocrisy of what they’ve said they believe in — their perverted version of their religion,” the former official said.