“Today the U.S. Attorney’s Office for the Southern District of New York executed a series of search warrants and seized the privileged communications between my client, Michael Cohen, and his clients,” Stephen Ryan, Cohen’s attorney, said in a statement “I have been advised by federal prosecutors that the New York action is, in part, a referral by the Office of Special Counsel, Robert Mueller.”

The news of the raid was first reported by the New York Times.

Cohen has come under scrutiny and been the subject of legal action after he said he used his personal funds to arrange a $130,000 payment just weeks before the presidential election to porn star Stormy Daniels, who alleges she had an affair with Trump over a decade ago. Daniels had told reporters from In Touch magazine and Slate that she’d had an affair with Trump in 2006, but she did not go public before the election.

The payment has been a source of a campaign finance violation complaint, but Cohen said the payment was lawful and he was never reimbursed by the Trump campaign. Daniels, who has sued Trump for an invalid disclosure agreement about the affair, expanded this suit last month to include Cohen, alleging he defamed her by questioning the veracity of her statements about the affair.

Ryan said the search was “completely inappropriate and unnecessary,” and resulted “in the unnecessary seizure of protected attorney client communications between a lawyer and his clients.”

Trump was still referring to Cohen as his attorney last week, when he was asked by reporters if he knew about the payment to Daniels, and why Cohen had made the payment. “You’ll have to ask Michael Cohen. Michael is my attorney. And you’ll have to ask Michael Cohen,” he said.