Donald Trump’s campaign is furiously pushing back against a super-PAC that a former ally launched on Thursday with the aim of damaging Trump’s rivals for the GOP nomination.

“Big league scam,” Trump campaign manager Corey Lewandowski told The Hill.

“We sent a cease-and-desist letter to this PAC in October and want nothing to do with this,” he said. “These guys are scam artists doing it for their own personal benefit and seeking to profiteer off Trump’s name. People should not give to this or any other super-PAC claiming to support Donald Trump for president.”

A pro-Trump super-PAC shut down in October after being disavowed by the Trump campaign.