Special counsel Robert Mueller's office has reportedly requested information from Cambridge Analytica, the data firm utilized by the Trump campaign during the 2016 presidential election.
The Wall Street Journal reports that Mueller's team has requested all emails from employees at the firm who worked with the campaign.
The request, which wasn't previously known, was voluntary, as was another request the firm complied with from the House Intelligence Committee, the newspaper reported.
Cambridge Analytica CEO Alexander Nix also interviewed with the House Intelligence Committee over video call this week, according to the report.
Nix was reported earlier this year to have been in contact with top Trump donor Rebekah Mercer about better organizing emails being released by WikiLeaks.
WikiLeaks chief Julian Assange tweeted that he could confirm that he was contacted by Nix prior to November 2016, and that Nix's request was declined.
It was reported that Nix was interested in obtaining the 33,000 emails deleted from Clinton's private server used during her time leading the State Department.
"I can confirm an approach by Cambridge Analytica [prior to November last year] and can confirm that it was rejected by WikiLeaks," Assange tweeted.