Top US Secret Service official Tony Ornato, who has become a figure of intense interest to the congressional committee investigating the January 6 Capitol attack, has retired from the agency.

Ornato was thrust into the center of the January 6 furor as an eyewitness to some of the most critical incidents involving Donald Trump in the hours leading up to the deadly assault on the US Capitol.

He began as head of Trump’s Secret Service detail but in an unprecedented move in December 2019 became deputy chief of staff in the White House.

In that capacity, he was drawn into the sights of the January 6 committee in its investigation of Trump’s role in inciting the Capitol insurrection. A former White House aide, Cassidy Hutchinson, in June testified publicly to the committee that Ornato had told her Trump had become “irate” when his security detail refused to drive him to the Capitol as the assault on Congress was beginning.

The attack aimed to prevent the congressional certification of Trump’s defeat to Joe Biden in the 2020 presidential election.

When his Secret Service driver insisted it was not safe to go, Trump lunged for the steering wheel and then grabbed the agent’s throat, Hutchinson testified Ornato had told her. Ornato reportedly denied the account through unnamed sources.

Hutchinson also revealed to the committee that Ornato had briefed top White House aides on January 6 itself that weapons were being carried among the crowd at the Capitol, including guns, knives and spears. Ornato has not denied that allegation.

On Monday, he confirmed that he had retired from the Secret Service, saying in a statement that he wanted to work in the private sector. He has already been interviewed twice by the January 6 committee, though the contents of his testimony have not been made public.

Among the areas of interest that the committee is likely to be pursuing is Ornato’s knowledge of how Trump’s vice-president, Mike Pence, was handled by Secret Service agents on January 6. As armed rioters were milling through the Capitol, shouting “Hang Mike Pence!”, the vice-president’s security detail tried to persuade him to evacuate the area.

“I’m not getting in the car,” Pence told the lead special agent, according to Philip Rucker and Carol Leonnig in their book I Alone Can Fix It.

At the White House, Ornato, who as deputy chief of staff had oversight over Secret Service decisions, told Pence’s national security adviser, Keith Kellogg, that the vice-president was going to be moved to the Maryland military facility Joint Base Andrews. Had he been evacuated, Pence would no longer have been able to certify Biden’s electoral victory, and Trump’s goal of postponing his defeat would have been fulfilled.

When Ornato said that the Secret Service would move Pence, Kellogg was adamant, Rucker and Leonnig reported. “You can’t do that, Tony,” Kellogg said. “Leave him where he’s at. He’s got a job to do. I know you guys too well. You’ll fly him to Alaska if you have a chance. Don’t do it.”