– A handful of GOP senators tried to stop President Donald Trump from firing Gordon Sondland, ambassador to the European Union who testified in the House impeachment hearings, but Trump relieved the diplomat of his post anyway, according to people briefed on the discussions.

The senators were concerned that it would look bad for Trump to dismiss Sondland and that it was unnecessary, since the ambassador was already talking with senior officials about leaving after the Senate trial, the people said. The senators told White House officials that Sondland should be allowed to depart on his own terms, reducing any political backlash.

But Trump chose instead to make a point by forcing Sondland out before the ambassador was ready to go. When State Department officials called Sondland on Friday to tell him that he had to resign that day, he resisted, saying that he did not want to be included in what seemed like a larger purge of witnesses, according to people informed about the matter.

If they wanted him gone that day, Sondland conveyed to the State Department officials then they would have to fire him. And so they did, ordering him recalled from his post effective immediately. Sondland’s dismissal was announced just hours after another impeachment witness, Lt. Col. Alexander Vindman, and his twin brother, Lt. Col. Yevgeny Vindman, were marched out of the White House by security officers and told their services were no longer needed.

The ousters came just two days after the GOP-led Senate acquitted Trump on two articles of impeachment. Outraged Democrats called the firings a “Friday night massacre” aimed at taking revenge against government officials who were forced to testify under subpoena.

The Republican senators who sought to intervene on Sondland’s behalf reached out to Mick Mulvaney, acting White House chief of staff, and Eric Ueland, legislative affairs director, to register their protests, according to one of the people informed about the conversations, who like others declined to be identified.

The senators did not express the same concern about Vindman, who is viewed less sympathetically by Trump’s allies. Republicans considered some of Vindman’s testimony overtly political and, in any case, believed it was untenable for him to remain on the staff of a president with whom he broke so publicly.

Trump on Saturday defended his decision to fire Vindman, calling the decorated Iraq war veteran “very insubordinate.”

“Fake News @CNN & MSDNC keep talking about ‘Lt. Col.’ Vindman as though I should think only how wonderful he was,” Trump tweeted, without explaining why he put the colonel’s rank in quote marks. “Actually, I don’t know him, never spoke to him, or met him (I don’t believe!),” he continued, “but, he was very insubordinate, reported contents of my ‘perfect’ calls incorrectly, & was given a horrendous report by his superior, the man he reported to, who publicly stated that Vindman had problems with judgement, adhering to the chain of command and leaking information. In other words, ‘OUT’.”

Trump offered no explanation for why Vindman’s twin brother, Yevgeny Vindman, who worked as a lawyer on the National Security Council staff, was also fired and escorted out of the White House complex at the same time even though he did not participate in the House hearings. Nor did the president mention his decision to recall Sondland.

The president’s dismissals of the Vindman brothers and Sondland opened a campaign of retribution just days after his Senate acquittal on charges of abuse of power and obstruction of Congress. Fresh from that political victory, Trump and his staff have made clear that they plan to “exact payback” on those they blame for his impeachment.

Vindman, a Ukraine expert on the NSC staff, and his brother were scheduled to remain at the White House until July but will now be sent back to the Defense Department. Sondland, a political appointee, will return to the United States and presumably leave government service.

A lawyer for Alexander Vindman said Trump’s Twitter messages contained “obviously false statements” about his client.

“They conflict with the clear personnel record and the entirety of the impeachment record of which the president is well aware,” said attorney David Pressman. “While the most powerful man in the world continues his campaign of intimidation, while too many entrusted with political office continue to remain silent, Lt. Col. Vindman continues his service to our country as a decorated, active duty member of our military.”

Alexander Vindman will report to the Pentagon until a previously scheduled assignment at the Army War College begins in July while Yevgeny Vindman, who goes by Eugene, will join the office of the Army general counsel.

“Throughout this process the Army leadership has been supportive of both Alex and Eugene in terms of their detail to the National Security Council and throughout the impeachment process,” said Michael Volkov, who represented Vindman when he testified in the impeachment inquiry. “The Army has been supportive and would never participate in the president’s desire for retaliation.”

Sondland and Vindman were key witnesses in the House impeachment hearings. Sondland, who was deeply involved in the effort to pressure Ukraine to announce investigations into Trump’s Democratic rivals, testified that “we followed the president’s orders” and that “everyone was in the loop.” Vindman, who was on Trump’s July 25 phone call with Ukraine’s president, testified that it was “improper for the president” to coerce a foreign country to investigate political ­opponents.