Dr. Ben Carson was “baffled” and “speechless” that one of his most loyal aides was walked out of the Housing and Urban Development after an op-ed resurfaced in which the aide criticized then-candidate Donald Trump, a source close to Carson said.

Carson, who is expected to be confirmed by the Senate, had no knowledge that Shermichael Singleton, was going to be escorted out of the building Wednesday until after it happened. The ordeal was first reported Thursday by the New York Times.

The source said that according to Carson, he was informed by HUD aide Sheila Daniels by phone while having lunch in Washington.