(JTA) — Turkish Jewish leaders say they are taking action after students at Istanbul’s Üsküdar American Academy reportedly performed the Nazi salute during a soccer game against Istanbul’s sole Jewish day school.

The students from the American Academy, one of Istanbul’s most elite schools, delivered the gesture at the game on Tuesday as a taunt following goals by the Ulus Jewish School team, according to reports on Twitter and in Avlaremoz, a Turkish Jewish media outlet.

Turkey’s official Jewish communal organization condemned the incident. The Jewish organization said that it was in contact with the American school’s board and that “necessary initiatives will be taken,” though it did not specify what those initiatives might be.

The American Academy is also investigating what unfolded at the game, according to a statement it issued on Wednesday.

“We would like to emphasize that we stand against all kinds of discrimination in accordance with our institutional and educational philosophy.” the statement said. “We have urgently contacted the school officials of Ulus Private Jewish High School, conveyed our regrets and initiated the necessary investigation.”

The incident has sent shockwaves through Istanbul’s Jewish community, which includes families with connections to both schools.

“As a Üsküdar American High School graduate, I do not want to believe this behavior of my school’s students towards the students of my son’s school.” one Jewish graduate, Roksi Levent, wrote on Twitter. “If it is true, I condemn it and I am deeply saddened to see my school come to this.”

Üsküdar American Academy was founded in 1876 by an American Christian missionary organization operating in the Ottoman Empire. The school teaches mostly in English and boasts that its graduates largely attend leading foreign universities. It does not have an affiliation with the U.S. government, as some other American schools abroad do, according to a spokesperson from the U.S. consulate in Istanbul.

Antisemitism is far from unheard of in Turkey. The Anti-Defamation League found in 2015 that 71% of adults held antisemitic views, according to an index the group developed. But public incidents of antisemitism in recent years have largely stemmed from Islamist and Turkic nationalist factions, rather than secularist bastions like Üsküdar American Academy. To some, the school’s Western orientation made the antisemitic gestures at the soccer game stand out.

“This Üsküdar American Academy is considered the second-most prestigious in Turkey,” Hay Eytan Cohen Yanarocak, a Turkish studies scholar at Tel Aviv University, told the Jewish Telegraphic Agency. “The level of education is very high, the children who are getting educated there are from the highest segment of society, or they are very clever and got scholarships to get into the school, or they are children of strong families, suggesting they are the children of the Turkish elite.

“It’s a Western type of education and you would not think that antisemitism would germinate there,” said Yanarocak, who graduated from the Ulus Jewish School and serves as an official advisor there for students who are considering Israeli universities. “The fact that this antisemitic incident took place in this spearheading institution instead of an ordinary school highlights the new low for antisemitism in Turkey.”

Antisemitic incidents at sporting events have been recorded around the world, including during professional soccer games in Europe and during high school sports events in the United States and beyond.

Betsy Penso, a graduate of Üsküdar American and a Turkish-Jewish journalist at Avlaremoz currently living in Israel, told JTA that during her time at the school, from 2006 to 2011, there were occasional tensions between Jewish and non-Jewish students over current affairs but no incidents like the one at the soccer match.

“I could hear ‘anti-Israel’ or ‘pro-Palestinian’ rhetorics but I cannot recall any incident [in which the] Holocaust was used as a humor mechanism at school,” Penso said. “I could have expected this happening in a different school but not mine. I could have expected this to happen in a different context but not against the students of a Jewish school.”

Now, she said, she and her fellow graduates are watching closely to see how their school handles the incident — and she hopes for swift and severe action.

“I was frustrated, I am still frustrated.” she said. “All of the alumni were shocked but of course Jews took it more personally for various reasons.… I really want these students to get expelled from the school. I also want a transparent communication and want to understand what, how and why this incident happened.”