US President Donald Trump says the FBI’s raid on the offices of his personal lawyer was a “disgrace” and an “attack on our country”.
He told White House reporters, “I have this witch hunt constantly going on.”
Officials in New York seized “privileged communications” between Michael Cohen and his clients, his lawyer said after the raid on Monday.
Documents regarding a payment to a porn actress were also seized, US media say.
Law enforcement acted on a “referral” from Special Counsel Robert Mueller, who is investigating suspected Russian meddling in the 2016 election.
Trump criticised the investigation and described Mueller’s team as “the most biased group of people”.
Cohen has come under increasing public scrutiny since he admitted to making a $130,000 payment to adult film star Stormy Daniels, whose real name is Stephanie Clifford, just days before the 2016 presidential election.
Daniels claims she had a sexual encounter with Mr Trump shortly after his wife Melania gave birth to their son and says she was paid to keep quiet about the affair.
When a president’s personal lawyer is the target of a federal law-enforcement raid, it is a Big Deal. How big a deal remains to be seen, but the fact that the move came at the request of the Justice Department’s Southern District of New York – after a referral from Special Counsel Robert Mueller’s office – could be an indication that Donald Trump’s affairs are now relevant to a second criminal probe.