The FBI’s investigation of Donald Trump’s former campaign manager, Paul Manafort, includes a keen focus on a series of suspicious wire transfers in which offshore companies linked to Manafort moved more than $3 million all over the globe between 2012 and 2013.

Much of the money came into the United States.

These transactions — which have not been previously reported — drew the attention of federal law enforcement officials as far back as 2012, when they began to examine wire transfers to determine if Manafort hid money from tax authorities or helped the Ukrainian regime close to Russian President Vladimir Putin launder some of the millions it plundered through corrupt dealings.