WASHINGTON

The U.S. Army's 18th Airborne Corps voiced "regret" Tuesday after it marked the anniversary of one of the bloodiest campaigns in American history by posting a colorized image of the war criminal who executed dozens of American prisoners of war.

"We regret the use of the photograph of Joachim Peiper," the Army division said in a statement on Facebook after having deleted the post with Peiper's photograph in what is meant to be a weeks-long remembrance of the campaign. "The intent was to tell the full story of the Battle of the Bulge."

The Pentagon also posted the photo and deleted it, but did not post a corresponding statement on the social media website.

Peiper commanded Nazi Panzer tank forces during a surprise attack on allied forces in the Ardennes Forest that began in the early morning of Dec. 16, 1944. American forces would bear the brunt of the casualties from the offensive, losing some 20,000 forces in the third deadliest campaign in U.S. history.

Peiper's armored division would execute nearly 85 American prisoners of war the day after the Nazi offensive began, amassing the U.S. detainees in a field before shooting them to death in what is known as the Malmedy massacre.

Shortly after the photo was posted on both the division and the Pentagon's Facebook pages, the outrage began pouring in, including from within the Department of Defense.

"I am dumbfounded by the decision to prominently display a Nazi on military social media on the 75th anniversary of the Battle of the Bulge," Brian Fickel, a Pentagon spokesman, said on his personal Twitter account, which stipulates that his opinions are his own, not the department's.

But on the corps' apology post, droves of respondents said there was "no need" to issue a mea culpa.

"Never apologize for telling and showing history as is. People are just too hypersensitive now. If we don't learn from history (even from the perspective of the 'enemy') then we are doomed to repeat," wrote one user. It is unclear why the user put "enemy" in quotes.

Another account echoed the sentiments of many, saying the corps should "keep up the good work." But not all were pleased.

"My father served with this unit in WWII and, contrary to the posting of too many here, he would have been mortified by the paean to Joachim Pieper. Pieper was a butcher, motivated by the racist fanaticism of the National Socialists. He was the reason so many Americans fought and died in those years. To celebrate him is to reveal your ignorance of history and your own bigotry," the user wrote.