Federal prosecutors have issued grand jury subpoenas to associates of former national security adviser Mike Flynn in recent weeks.

Prosecutors issued the subpoenas seeking business records as part of the FBI's larger probe into meddling by the Russian government into the 2016 presidential election, according to a CNN report.

The subpoenas were issued by U.S. Attorney Dana Boente, who was recently appointed to be the acting assistant attorney general for the national security division — a post that oversees the FBI's Russia investigation.

Boente is still the U.S. Attorney for the Eastern District of Virginia, which includes the Alexandria office from which the subpoenas were issued.

The associates who received the subpoenas worked with Flynn on contracts after he was forced out as director of the Defense Intelligence Agency in 2014.

Flynn's handling of how he disclosed payments from clients tied to Russia and Turkey are also reportedly under investigation.

Flynn resigned as President Trump's national security adviser in February after revelations that he failed to disclose conversations he had with Russian Ambassador Sergey Kislyak.

The news of the subpoenas come just hours after Trump fired FBI Director James Comey, who was overseeing the broader probe.