The Justice Department inspector general has begun examining the abrupt departure this month of the U.S. attorney in Atlanta after then-President Donald Trump complained officials in Georgia were not doing enough to find election fraud, according to people familiar with the matter.

The investigation into the sudden resignation of Byung J. “BJay” Pak by Inspector General Michael Horowitz appears to be in its early stages. Investigators have not yet talked to Pak, and it is unclear how broad their inquiry will be, the people familiar with the matter said. Like others, they spoke on the condition of anonymity to discuss an ongoing probe.

Pak unexpectedly announced Jan. 4 that he was stepping down that day as the U.S. attorney for the Northern District of Georgia, surprising many in his office. Trump then bypassed Pak’s top deputy in selecting a temporary replacement, raising questions among legal observers about the possibility of political interference in law enforcement work.

Pak’s resignation came a day after The Washington Post reported on an extraordinary call in which Trump urged Republican Brad Raffensperger, the Georgia secretary of state, to “find” enough votes to overturn his election defeat in that state. Legal scholars said the request from Trump was an obvious abuse of power that might warrant criminal investigation. In the same conversation, Trump cited a “never-Trumper U.S. attorney” in Georgia — seemingly a reference to Pak — and hinted vaguely and baselessly that Raffensperger’s refusal to act on his unfounded fraud claims constituted a “criminal offense.”

Pak declined to comment for this story, as did a spokeswoman for Horowitz. On Thursday, the law firm Alston & Bird announced that Pak would be joining as a partner in its litigation and trial practice group in the Atlanta office. He had worked at the firm previously and had served as a state lawmaker before Trump appointed him as a U.S. attorney in 2017.

The circumstances of Pak’s departure remain something of a mystery. Two people familiar with the matter said Pak received a call from a senior Justice Department official in Washington that led him to believe he should resign. Trump had been upset with what he perceived as the agency’s lack of action on his unfounded claims in Georgia and across the country, people familiar with the matter said at the time.

Trump then appointed Bobby Christine, the top federal prosecutor in the Southern District of Georgia, to replace Pak, and Christine brought with him to the new office two prosecutors who had recently been assigned to monitor possible election fraud. Spokespeople for the U.S. attorney’s offices in the Northern and Southern Districts of Georgia declined to comment.

The moves further alarmed legal observers. By default, the job would have passed to Kurt Erskine, a longtime federal prosecutor and Pak’s deputy. And some observers questioned the need to bring in prosecutors from a smaller district to help in Atlanta.

If Christine intended to make some move to support Trump’s claims of voter fraud, though, that effort appears to have petered out. According to an audio recording obtained by the Atlanta Journal-Constitution, he declared on a call with his staff before Trump left office that “there’s just nothing to” the few claims of fraud the office was examining.

“Quite frankly, just watching television, you would assume that you got election cases stacked from the floor to the ceiling,” Christine said, according to the Atlanta newspaper. “I am so happy to find out that’s not the case, but I didn’t know coming in.”

A Justice Department official said the prosecutors he brought in — Joshua S. Bearden and Jason Blanchard — have since returned to their home office. It was unclear whether the inspector general would examine their actions or Christine’s as part of the probe surrounding Pak’s departure. A Justice Department memo issued Wednesday said all the Trump-appointed U.S. attorneys who remained in their jobs — which would include Christine — have been asked to stay on “for the time being.”