In an interview with a Philadelphia radio station on Wednesday, Donald Trump Jr. accused the Democrats of rigging their primary system.
“If Republicans were doing that, they’d be warming up the gas chamber right now,” he said.
The ADL, an international anti-Semitism organization, tweeted Thursday that “trivialization of the Holocaust and gas chamber is NEVER OK.”
The group then tweeted that its members hoped Trump Jr. understood the “insensitivity and hurt” caused by his joke and asked for an apology.
The Trump campaign did not immediately respond to a request for comment.