One of special counsel Robert Mueller's top prosecutors is leaving the team, the latest indication that the Russia investigation is winding down.

Andrew Weissmann, who is widely regarded as Mueller's "pit bull," is departing Mueller's office and the Justice Department in the next couple weeks to work at New York University, according to NPR.

Weissmann led the federal inquiry's case against former Trump campaign chairman Paul Manafort, who over the past week was sentenced to roughly seven and a half years in prison for conspiracy and fraud.

Weissmann has come under fire by conservatives for actions that show the potential for bias, including attending Hillary Clinton's 2016 election night party and praising former acting attorney general Sally Yates in an email after she refused to defend his initial travel ban. Weissmann was also one of the Justice Department officials who was informed of the anti-Trump dossier by former DOJ official Bruce Ohr before joining Mueller's team.

The timing of that Weissman's departure comes after recent reports suggested the Russia probe would soon wrap up, but three U.S. officials told Reuters Mueller’s team has funding until the end of September, indicating that the inquiry could last for several more months.

Still, there have been other high-profile departures indicating that the Russia investigation is almost done.

[Related: House votes unanimously to release Mueller report to public]

Special Agent in Charge David Archey, Mueller's top investigator, left Mueller's team to become the head of the FBI's office in Richmond earlier this month.

Brandon Van Grack and Kyle Freeny, two prosecutors who were also part of the Manafort case, parted ways with Mueller late last year to return to their positions at the Justice Department

So far, 34 people and three companies have been indicted or taken guilty pleas as part of Mueller's investigation, but none of them have to do with Russian collusion.

President Trump has repeatedly called Mueller's investigation a "witch hunt."