Michael Reynolds/Pool/Getty Images Shermichael Singleton was an aide to Ben Carson, President Donald Turmp's choice to be secretary of Housing and Urban Development.

WASHINGTON ― The Trump administration fired a top aide to Housing and Urban Development secretary nominee Ben Carson Thursday, after discovering that he once wrote columns critical of Donald Trump.

The New York Times reported that Shermichael Singleton, 26, was escorted out of HUD headquarters by security officials. The Huffington Post also confirmed the incident with an agency civil servant who said they were shocked and dismayed by the firing.

Singleton was one of the few black Republicans in the Trump administration. He has worked on other GOP campaigns, including Carson’s 2016 bid.

But he also wrote pieces that criticized Trump. In March 2016, for example, he wrote a column for The Hill that lamented Trump’s rhetoric toward people of color:

I would like to see nothing more than a Republican win the White House this November, but I have to seriously ask myself if Trump is capable of doing just that. I have attempted to remain hopeful and a part of me will continue do so, but Trump’s antics make it impossible for any Republican — particularly a minority — to defend him, which can only mean bad things for the future of the GOP.

Officials noticed the pieces during the vetting process, according to The New York Times, and asked him about them. Although Singleton said he regretted writing it, officials told him he would not get a permanent position at HUD because of them.

Trump has not taken well to people who once criticized him. Elliott Abrams, a veteran Republican national security official, was taken out of consideration for a top job at the State Department after the president found out that he had opposed him during the campaign. Trump did so over the objections of Secretary of State Rex Tillerson, who wanted Abrams on his team.

Singleton did not return a request for comment. HUD confirmed to the Times that as of Thursday, he is no longer working at the agency.

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