The FBI has conducted a pre-dawn raid on the Virginia home of Donald Trump's former campaign chairman Paul Manafort, US media report.
Federal agents are said to have seized files and other material on 26 July, a day after Mr Manafort voluntarily met the Senate Intelligence Committee.
Mr Manafort left the Trump campaign over questions about his foreign ties.
The FBI is leading one of several investigations into alleged Russian meddling in last year's US election.
Special counsel Robert Mueller, who is head of the FBI investigation, left Mr Manafort's home with "various records", the Washington Post reported.