(CNN) A government watchdog is assessing allegations of retaliation against State Department employees after CNN reported last week that multiple staffers had retained attorneys to represent them over concerns they had been assigned to low-level jobs because of their involvement in executing policies that are unpopular with the current administration.

The issue drew attention from key Democratic lawmakers, who wrote a letter urging the agency's independent inspector general to conduct an "immediate review" of personnel practices after being contacted by whistleblowers who corroborated the CNN report.

Sarah Breen, a spokeswoman for the State Department Inspector General's office, told CNN the office received the letter and was "conducting preliminary work at this time" to "assess the allegations."

"Our staffs have been made aware of credible allegations that the State Department has required high-level career civil servants, with distinguished records, serving administrations of both parties, to move to performing tasks outside their area of substantive expertise," Reps. Eliot Engel, the top Democrat on the House Foreign Affairs Committee, and Elijah Cummings, the top Democrat on the House Oversight Committee, wrote in the letter sent Friday to the State Department's inspector general.

"At the very least, this is a waste of taxpayer dollars," they wrote. "At worst it may constitute impermissible abuse and retaliation."

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