A Wisconsin school district says it is investigating a photo of a large group of male high school students giving what looks like the Sieg Heil, a victory salute used by Nazis.

Baraboo Superintendent Lori Mueller told Wisconsin Public Radio and The Associated Press that she became aware of the photo's existence on Monday after it began circulating on social media. The photo, of Baraboo High School students, was reportedly taken last spring.

WPR and the AP say the school district and Baraboo police are investigating.

The photo emerges barely two weeks after an armed assailant entered a Pittsburgh synagogue and killed 11 people in the worst single attack on Jews in U.S. history.

"The Baraboo School District is a hate-free environment where all people, regardless of race, color, religion, creed, sex, sexual orientation, gender identity, national origin or ancestry, are respected and celebrated," Mueller said in a statement.

The Baraboo School District says the photo wasn't taken on school property or at a school-sponsored event. Photographer Pete Gust hosted the photo on a page on his website titled "BHS Prom Pic's."

The district sent a letter to students' parents on Tuesday, informing them of the photo and of the students' "extremely inappropriate gestures."

"If the gesture is what it appears to be, the district will pursue any and all available and appropriate actions, including legal, to address this issue," the letter says.

As WPR reports,

"Morgan Springer graduated from Baraboo High School in 2018 and said she was there when the photo was taken. She said the photographer asked the boys to 'give some kind of like 'Yeah!' symbol' but she didn't believe the photographer indicated they should do the Nazi salute. 

'About 99 percent of the guys all shot up the Nazi salute,' Springer wrote in an email to WPR. 'I personally knew a few of the students, who are current seniors at BHS who didn't do it ... They were all shocked that it was even happening.'

'Even as they did it and pictures were being taken, nobody tried to stop them,' Springer added. 'Parents and even the professional photographer just kept taking the picture and were even laughing because they were looking at it as a joke and even saying, 'Oh, those silly kids.""

A mother of a Baraboo High School student told WPR that the gesture meant something different altogether: It's a common gesture at Friday night football games, she said.

One student in the group's front row made what appears to be a "white power" gesture.

Gust deleted the photo from his website and replaced it with a text post saying that the photo had been deleted "due to the malevolent behavior on the part of some in society."

"To anyone that was hurt I sincerely apologize," he wrote.

Baraboo, about 100 miles northwest of Milwaukee, is a mostly white city — 93 percent of its residents identify as "white only," according to the U.S. Census Bureau. According to the National Center for Education Statistics, over 85 percent of the school's 992 students from the 2015-2016 school year were white.

There are no synagogues in Baraboo and a local ABC affiliate reports that a week before midterm elections, "area residents received white nationalist propaganda in their mailboxes."

"The single-page fliers with the headline 'White Lives Matter' linked to websites promoting nationalist and anti-Semitic views," ABC reported.

Journalist Jules Suzdaltsev, who tweeted the image out early Monday morning, said he spoke to many current and former students throughout the day.

"Nearly all of the stories echo the same basic theme: the community as a whole has a lot of casual & jokey racism, homophobia, and transphobia that is accepted as a part of life," he tweeted.

"We need to explain what is the danger of hateful ideology rising," the Auschwitz Mueseum, which preserves the site of the former German Nazi Auschwitz concentration and extermination camp, tweeted. "Auschwitz with its gas chambers was at the very end of the long process of normalizing and accommodating hatred."

Wisconsin's governor elect, Democrat Tony Evers, told WPR and the AP Monday the students' actions have "no place in Wisconsin."

"Intolerance and bigotry must never be tolerated, in our schools or anywhere else," the governor elect said, noting that he will be in touch with school officials.

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