How did an infamous Nazi war criminal — his collar emblazoned with Waffen-SS lightning bolts — wind up featured prominently on the Facebook page of a famed U.S. Army unit?

That’s the question being put to the XVIII Airborne Corps, based in Fort Bragg, North Carolina, who shared the image of Nazi field officer Joachim Peiper on Monday evening as part of an ongoing series of posts about XVIII Airborne Corps’ final offensive campaign during World War II’s Battle of the Bulge 75 years ago.

“The fate of his beloved nation rested on his ability to lead his men through the American lines,” XVIII Airborne Corps wrote of Peiper, who is responsible for slaughtering scores of Americans.

The post, which has since been edited, was reshared widely by other military units, even by the Department of Defense’s own Facebook.

It’s a particularly delicate matter, given the surge in far-right extremism around the world. It comes comes on the heels of other similarly embarrassing incidents for the U.S. military, which has fended off accusations that it’s failing to enforce its own policies designed to keep extremism out of the ranks. Over the weekend, military officials said they were investigating whether a group of naval and Army students flashed white power symbols on TV during a football game. And in the last few years, around a dozen active-duty service members have been exposed as white nationalists or neo-Nazis.

By Tuesday morning, the post had been flooded with comments accusing the XVIII Airborne Corps of being “fanboys” for Peiper by glamorizing him. In response to one critic, the unit defended themselves by insisting they were simply using a “technique of effective storytelling.” “Sometimes in movies, the movie will create a sense of tension by introducing the bad guy,” they wrote.

One member of the U.S. military, who first surfaced the post on Monday, said he was “dumbfounded” by it.

The colorized image originated from a Slovakian fascist gamer’s website, as observed by journalist Corey Pein, who matched the watermarks in the picture.

The unit has since used Facebook’s edit function to swap out Peiper’s portrait for scenes from the battlefield, and edited the text to refer to the Nazi military officer as an “evil war commander.”

“We regret the use of the photograph of Joachim Peiper,” they wrote in a statement Tuesday morning. “The intent was to tell the full story of the Battle of the Bulge, which will continue here, by explaining the incredible odds that were stacked up against the American Soldier by the time the reserve was called in on 18 Dec.”

The Pentagon did not respond to VICE News’ request for comment.