Donald Trump Jr. defended remarks about the media “warming up the gas chamber” on Thursday, clarifying to NBC News that he was referring to capital punishment and not the gas chambers used by Nazis to murder Jews.

"Without the media, this wouldn't even be a contest, but the media has built her up, they've let her slide on every indiscrepancy, on every lie, on every DNC game, trying to get Bernie Sanders out of the thing,” the Republican nominee’s son said in a radio interview on 1210 WPHT in Philadelphia Thursday. "If Republicans were doing that, they'd be warming up the gas chamber right now.”

The remark drew sharp criticism from the Anti-Defamation League, which advocates against hate speech.

“We hope you understand the sensitivity and hurt of making Holocaust jokes,” the organization tweeted at Trump from its official account. “We hope you retract.”

.@DonaldJTrumpJr: We hope you understand the sensitivity and hurt of making Holocaust jokes. We hope you retract.https://t.co/jL2ZC9Z8pH — ADL (@ADL_National) September 15, 2016

Let our news meet your inbox. The news and stories that matters, delivered weekday mornings. This site is protected by recaptcha

Trump Jr. told NBC News’ Katy Tur that he stood by his point, but that he meant to refer to executions rather than the Holocaust. He said he normally uses the phrase “electric chair” to make the same point.

The campaign followed up as well with a statement blaming the press for misinterpreting his remarks.

"The liberal, dishonest media is so quick to attack one of the Trumps that they never let the truth get in the way of a good smear," Trump spokesman Jason Miller said in a statement. "Don Jr. was clearly referring to capital punishment to make the case that the media continues to take words out of context in order to serve as the propaganda arm of the Hillary Clinton campaign — something that's only gotten worse as Trump's poll numbers have improved."

In a statement provided by the Democratic National Committee, Pennsylvania Democratic Party chair Marcel L. Groen implied Trump's "gas chamber" remark was a dogwhistle to anti-Semitic supporters, some of whom have used Holocaust imagery to harass Jewish journalists on social media.

Related: Donald Trump's 'Star of David' Tweet About Hillary Clinton Posted Weeks Earlier on Racist Feed

"It is horrifying that Donald Trump Jr. thinks it is appropriate to casually joke about the Holocaust — and even worse, he is defending it, saying it isn't anti-Semitic," Groen said. "My grandparents died in Auschwitz, as did some of my aunts and uncles. They died in gas chambers. As a naturalized American citizen whose parents came to this country after World War II, I ask Trump to stop trying to reach out to the worst of us; the bigots and the anti-Semites."

Trump Jr. and his father have retweeted extremist users at various pointsin the campaign, including an incident in which the senior Trump tweeted an image of Clinton, a Star of David, and a pile of money, that reportedly originated on a racist Twitter account. Despite its apparent source, Trump claimed the image was a "sheriff's star."

The comment came on a busy day for Trump Jr., who also drew attention for contradicting his father’s excuses on not releasing his tax returns.

Donald Trump has said repeatedly that he won’t release any tax returns for himself or his business — which breaks from four decades of precedent and could keep potential conflicts in the dark — because of an ongoing audit.

But his son contradicted him on Thursday, instead seeming to imply that the campaign feared the public might find politically damaging information.

"Because he's got a 12,000-page tax return that would create … financial auditors out of every person in the country asking questions that would detract from (his father's) main message,” Trump Jr. told the Pittsburg Tribune-Review in an interview published Thursday.

Topping off the day, Trump Jr. also tweeted that “the new aristocrats are in DC” and taking from “hardworking Americans,” a reference that struck some observers as odd coming from the son of a billionaire whose father was also wealthy.

Critics passed around a 2012 tweet by Trump Jr. that had gone viral earlier thanking his family “greenskeeper” for skipping his own sister’s wedding to work for them. “Luv loyalty 2 us,” he added. It was not clear whether it was intended as a joke.