WASHINGTON (AP) — Congressional Democrats say the State Department watchdog fired by President Donald Trump last week was investigating possible impropriety in a massive arms sale to Saudi Arabia last year, adding new questions to the watchdog’s abrupt dismissal.

Democrats said Monday that ousted Inspector General Steve Linick was probing how the State Department pushed through a $7 billion Saudi arms sale over congressional objections. Democrats previously suggested the dismissal might have been tied to Linick’s investigation of allegations that Secretary of State Mike Pompeo may have improperly ordered staff to run personal errands for him.

Linick’s dismissal late Friday comes amid broader concerns over Trump’s removal of inspectors general at various executive branch departments. Trump has said he had lost confidence in those fired but has not given specific reasons, which lawmakers from both parties have criticized.

Pompeo told The Washington Post on Monday that he had recommended to Trump that Linick be removed because he was “undermining” the State Department’s mission, but he would not address specifics except to say it was not in retaliation for any investigation.

“It is not possible that this decision, or my recommendation rather, to the president rather, was based on any effort to retaliate for any investigation that was going on, or is currently going on,” Pompeo told the Post, adding that he did not know if Linick’s office had been looking into possible impropriety on his part.

Under Secretary of State for Management Brian Bulatao told the Post that confidence in Linick had begun to wane after leaks to the media last year about an IG investigation into political retaliation against career employees by political appointees. When released, that report was critical of several political appointees for having acted against career officials deemed insufficiently loyal to Trump.

Trump confirmed Monday that he fired Linick at Pompeo’s request.

“I have the absolute right as president to terminate. I said, ‘Who appointed him?’ And they say, ‘President Obama.’ I said, look, I’ll terminate him,” Trump said at the White House.

Eliot Engel, the chairman of the House Foreign Affairs Committee, said he was troubled that Linick was fired before the completion of the Saudi investigation.