(CNN) With the indictment Thursday of associates of President Donald Trump's personal attorney, Rudy Giuliani, New York federal prosecutors are yet again behind a criminal case that threatens Trump's inner circle.

That has raised fears in law-enforcement circles that the head of the office, Manhattan US Attorney Geoffrey Berman, could be in the crosshairs of the President. But Justice Department officials say privately that they believe the high-profile nature of the case and the potential for political blowback if Berman were removed may help secure his position.

In recent months, the name of a top Justice Department official -- Ed O'Callaghan, a former New York federal prosecutor -- has been discussed in Washington as a possible nominee to replace Berman, according to Justice Department officials.

But the case charged Thursday has put a chill on any efforts to advance O'Callaghan for the job, these people said.

The case against the Giuliani associates -- in which four men are charged with allegedly funneling foreign money into US elections -- and its political implications, given that two of the men are central to the impeachment inquiry in the House, has put a spotlight on Berman. But it is just the latest in a string of inquiries from the office that have taken aim at Trump or his allies.

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