Special Counsel Robert S. Mueller is investigating the finances and business dealings of Jared Kushner, President Trump’s son-in-law and adviser, as part of the probe into Russia’s interference in the 2016 presidential election, according to officials familiar with the matter.

FBI agents and federal prosecutors have also been examining the financial dealings of other Trump associates, including former national security adviser Michael Flynn, former campaign chairman Paul Manafort and Carter Page, who was listed as a foreign policy adviser for the campaign.

The Washington Post had earlier reported that investigators were scrutinizing separate meetings that Kushner held with Russians in December — first with Russian ambassador Sergey Kislyak and then with Sergey Gorkov, the head of a state-owned Russian development bank. At the time of that report it was not clear that the FBI was investigating Kushner’s business dealings.