WASHINGTON — FBI Director Christopher Wray told agency staffers that he was concerned about “a potential conflict of interest” involving the selection of the bureau’s new headquarters in Maryland, according to an email obtained by NBC News.

On Thursday, the General Services Administration confirmed that the FBI’s new home would be in Greenbelt, about 13 miles northeast of Washington, seeming to bring to an end a drawn-out and politically fraught site selection process. Two other finalists were Springfield, Virginia, and Landover, Maryland.

In his unusually pointed letter to staffers, Wray said the FBI has “concerns about fairness and transparency in the process and GSA’s failure to adhere to its own site selection plan,” adding that a senior GSA executive overruled a board decision and picked land that is owned by the executive’s previous employer, the Washington Metropolitan Area Transit Authority.

A three-member panel had initially determined that Springfield, Virginia, was the best location. The decision of a political appointee overseeing the process to reject career officials’ “unanimous” recommendation, Wray wrote, wasn’t “‘inherently inappropriate,’ but it is ‘exceedingly rare.’”

“In particular, the FBI observed that, at times, outside information was inserted into the process in a manner which appeared to disproportionately favor Greenbelt, and the justifications for the departures from the panel were varied and inconsistent,” Wray said.

Politicians from Virginia echoed Wray’s concerns about the process and voiced frustration after years of fighting with their Maryland counterparts to host the new headquarters. Some called for an investigation and for the GSA’s decision to be reversed.

“It is clear that this process has been irrevocably undermined and tainted, and this decision must now be reversed,” said a statement from both of the commonwealth’s senators, eight of its House members and Gov. Glenn Youngkin.

Sen. Mark Warner, D-Va., said he plans to call for an inspector general’s investigation, saying, “This process has been rotten.”

“Yes, there should be an IG investigation, and we will call for one, but my hope would be the administration would realize this process has been rotten,” Warner told NBC News, “And, you know, the folks who work at the FBI deserve better answers; the American taxpayers deserve better answers.”

Sen. Tim Kaine, D-Va., told NBC News that he and other Virginia lawmakers were “really disappointed” by the decision and “knew that there had been political calculation to change the criteria.”

“It should definitely be reversed,” Kaine added.

Sen. Ben Cardin, D-Md., said the senators are “just wrong on that.”

“The GSA made the right decision based upon the taxpayers, based upon the mission, the availability of the site, the ability of the site to handle the growth that’s necessary,” Cardin said. “It’s the best transit-related location. I mean, the list goes on and on and on why they chose that site.”

The Biden administration defended the process as “fair and transparent.” White House principal deputy press secretary Olivia Dalton told reporters that Greenbelt was the cheapest location with the best access to public transit for FBI workers.

GSA Administrator Robin Carnahan also defended the process.

“GSA and FBI teams have spent countless hours working closely together over many months, so we’re disappointed that the FBI Director is now making inaccurate claims directed at our agency, our employees, and our site selection plan and process,” she said in a statement. “Any suggestion that there was inappropriate interference is unfounded.”

Carnahan said the GSA has tried to “incorporate the FBI’s feedback and appropriately address their concerns” throughout the process.

However, Wray said the FBI’s concerns about the process “remain unresolved,” although Congress “will control the next steps.”

“There are still a lot of open questions, and we’ve still got a long way to go,” he said. “But ultimately, our focus will remain on doing everything we can to ensure the FBI has a Headquarters that best meets the needs of our workforce, our mission, and the American people.”