"A review of the facts and circumstances of this case, including newly discovered and disclosed information, indicates that Mr. Flynn’s statements were never 'material' to any FBI investigation," read the motion to dismiss the two-and-a-half year old criminal prosecution.

The move to dismiss the case was approved by Barr at the urging of a longtime federal prosecutor he assigned in January to conduct a review of the matter, Jeffrey Jensen, the U.S. Attorney in St. Louis.

"Through the course of my review of Gen. Flynn’s case, I concluded the proper and just course was to dismiss the case," Jensen said in a statement. "I briefed Attorney General Barr on my findings, advised him on these conclusions, and he agreed."

The bombshell court filing asking U.S. District Judge Emmet Sullivan to dismiss the case bore the signature of only one prosecutor: U.S. Attorney for the District of Columbia Timothy Shea, a former Barr aide named to the post in January.

Moments before Shea's filing, the top prosecutor in the Flynn case withdrew abruptly and without explanation. Brandon Van Grack, who served as one of special counsel Robert Mueller's top lawyers and remained on the Flynn case even after Mueller's office closed down, signaled his exit from the case in a terse, one-sentence filing with U.S. Sullivan.

In another sign of discord, the prosecutor who handled the matter alongside Van Grack over the past year — Assistant U.S. Attorney Jocelyn Ballentine — was also absent from the filing seeking to drop the case.

After switching defense teams last year, Flynn began leveling a series of increasingly strident attacks on the prosecution, culminating in a motion in January to withdraw his guilty plea altogether.

Van Grack's withdrawal came four days before a court deadline for the prosecution to respond to an ongoing effort by Flynn's defense team to have the case against him dismissed on the grounds of egregious government misconduct.

In recent weeks and months, Flynn's defense — headed by Texas lawyer Sidney Powell — had escalated its attacks on Van Grack personally, alleging that he withheld evidence favorable to Flynn in defiance of an order from Sullivan requiring the prosecution to turn over such material.

A defense filing two weeks ago accused Van Grack of "incredible malfeasance" and of coercing Flynn's guilty plea in the fall of 2017 by making "baseless threats" to indict Flynn's son, Michael G. Flynn Jr.

Van Grack was the only member of Mueller's prosecution squad to take up a Justice Department leadership position after the Russia probe closed down, assuming a role last March overseeing the department's enforcement of the foreign-agent registration laws and other efforts to combat foreign influence in the U.S.

It was not immediately clear Thursday whether Van Grack was continuing in that capacity or leaving his post altogether. The court filings he submitted Thursday still bore his title as chief of the Foreign Agent Registration Act Unit.

The filings also did not indicate whether Van Grack was directed to withdraw from the Flynn case or elected to do so.

The dismissal of the case is subject to Sullivan's approval, but the Justice Department's filing Thursday suggested that should be more or less a formality. It would be extraordinary for a judge to order prosecutors to proceed with a case they are seeking to drop.

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