German police began an investigation into an antisemitic tweet sent to Israeli football player Almog Cohen after he got a red card during match between Ingolstadt and FC Union Berlin.

Cohen is the captain of Ingolstadt and has lived in Germany for nine years. He also plays for the Israeli national team.

The tweet was posted during the match and said Cohen should vanish into “the chamber,” a reference to the gas chambers used by the Nazis in the Holocaust.

Both clubs immediately condemned the tweet with the hosting club, Union Berlin, filing an official complaint with the police.

“I’m ashamed of such Union fans,” club president Dirk Zingler said in a statement. “FC Union stands for humanistic and democratic values. Anyone who doesn’t share these values has no place in our club or our stadium.”

Cohen tweeted a message of thanks to his supporters.

“As a Jewish professional football player in Germany I just want to say: I am very proud of my heritage and representing my country in the second division and being captain of Ingolstadt,” he wrote.

“A big thank you to my club which gives me the support and therefore the strength to master any situation.”