Mueller's team used phone records to probe Cohen's location during Stormy Daniels payoff saga: Search warrants
President Donald Trump’s former attorney Michael Cohen arrives for sentencing. (AFP / COREY SIPKIN)

Investigators obtained a mountain of evidence against Michael Cohen, according to newly revealed court documents, and suspected early on that President Donald Trump's personal lawyer was a foreign agent.

The Southern District of New York released search warrants relating to Cohen on Tuesday as part of a court order, and the documents show the FBI appears to have gathered considerable evidence related to campaign finances -- some of which is still being withheld from the public, reported Bloomberg.

Special counsel Robert Mueller started eying Cohen two months after he was appointed by deputy attorney general Rod Rosenstein, and the FBI obtained a search warrant July 18, 2017, for the former Trump Organization's email records dating back to Jan. 1, 2016 -- and then another one for emails from mid-2015.

The second affidavit, from Feb. 28, 2018, said investigators were seeking evidence of conspiracy to defraud the United States and that Cohen may have been acting as an unregistered foreign agent.

Journalist Marcy Wheeler said investigators may have been interested in Cohen's work with a Kazakhstan bank and Korean airspace company, as well as his work for Columbus Nova, which has been linked to Russian oligarch Viktor Vekselberg.

"It appears that Mueller’s worries about Trump’s closest associates acting as spies wasn’t limited to (Paul) Manafort and (Michael) Flynn, but extended, too, to his personal lawyer," Wheeler wrote. "And Mueller already had evidence of that fact by July 18, 2017."

Several portions of the affidavits are listed as “The Illegal Campaign Contribution Scheme,” and they're each followed by more than 18 redacted pages.

Cohen has said after he pleaded guilty that Trump directed illegal payoffs to women who claimed to have been his mistress, and the newly revealed warrants show investigators obtained location data on two of Cohen's cell phones from the five weeks ahead of the 2016 presidential election.

Investigators also obtained cell phone location data dating from Jan. 1, 2018.

Those two time periods line up with publicly known events surrounding the payoffs to former porn actress Stormy Daniels, who had been discussing in the weeks prior to the election coming forward with an account of her affair with Trump.

Cohen pleaded guilty to arranging a $130,000 payoff to Daniels, which was eventually revealed in a January 2018 article in the Wall Street Journal, and it appears investigators wanted to know exactly where the attorney was during that period.

Edit: A previous version of this story reported that Columbus Nova was "ultimately controlled" by Viktor Vekselberg, which the company disputes: "Columbus Nova itself is not now, and has never been, owned by any foreign entity or person including Viktor Vekselberg or the Renova Group," the company said in a statement. "The same is true with regard to all investment management companies under the Columbus Nova umbrella."