President Joe Biden lambasted Republican frontrunner Donald Trump for comparing his political enemies to “vermin,” saying the language evoked that of Nazi Germany.

“A specific phrase — it’s just a specific meaning,” Biden said Tuesday at a political fundraiser in San Francisco. “It echoes language you heard in Nazi Germany in the ‘30s. And this isn’t even the first time.”

Trump, at a Veterans Day event in Claremont, New Hampshire, on Saturday, vowed to “root out the communists, Marxists, fascists and the radical left thugs that live like vermin within the confines of our country.”

Biden said that language and Trump’s recent remarks in an interview saying that immigrants were “poisoning the blood of our country” echoed fascist talking points. He also criticized Trump for mocking the assault on the husband of former House Speaker Nancy Pelosi, who has for decades represented California, saying that “political violence is never acceptable.”

“Damn, he shouldn’t be president,” Biden said.

Biden has criticized extremist rhetoric and urged Americans to reject political violence — often singling out Trump and his supporters as a particular threat to US democratic institutions. Biden and Trump are barreling toward a potential general-election rematch, with the former president the clear frontrunner among the GOP field. Several recent polls have shown Biden trailing Trump both nationally and in key swing states.

Biden said last week’s elections were evidence that US voters supported his message, even if polls showed that Democrats faced long odds. He said that Democratic victories in Virginia’s state-level House and Senate elections forced Republican Governor Glenn Youngkin to abandon his own White House ambitions, and celebrated the election of former aide Gabe Amo to represent Rhode Island in the US Congress.

“Sounds like a pretty good day for Joe Biden,” the president quipped.