FBI agents raided the home in Alexandria, Va., of President Trump’s former campaign chairman, arriving in the pre-dawn hours late last month and seizing documents and other materials related to the special counsel investigation of Russian meddling in the 2016 election.

The raid, which occurred without warning on July 26, signaled an aggressive new approach by special counsel Robert S. Mueller III and his team in dealing with a key figure in the Russia inquiry. Manafort has been under increasing pressure as the Mueller team looked into his personal finances and his professional career as a highly paid foreign political consultant. … The search warrant indicates that investigators may have argued to a federal judge that they had reason to think Manafort could not be trusted to turn over all records in response to a grand jury subpoena.