Maccabi Haifa fans were allegedly subjected to anti-Semitic insults by some Union Berlin supporters at the city's Olympic Stadium during Thursday's Europa Conference League match.

Union Berlin beat the Israeli champions 3-0, but according to the Youth Forum of the German-Israeli Society Berlin-Potsdam, there were ugly scenes in the stands

"On the terraces, we were threatened by Union fans, pelted with beer", the Forum wrote on Twitter, adding that members of their group were subjected to anti-Semitic insults "among other things".

The Forum also alleges that "a Union fan tried to set fire to the Israeli flag... which was fortunately quickly prevented by civilian police officers."

However, on Friday morning, the group tweeted a "thank you for the wave of solidarity online and to the Union fans who showed solidarity with us in the stadium".

Union asked for help via Twitter to identify the alleged perpetrators.

Berlin police could not provide any information about the incident when asked by AFP subsidiary SID.

The game was switched from Union's Alten Foersterei ground to the Olympic Stadium, home of rivals Hertha Berlin, to meet UEFA requirements.