Steve Bannon, a longtime ally of former US president Donald Trump, turned himself in to an FBI field office in Washington on Monday, after being charged with contempt of Congress.

Bannon was surrounded by photographers and a protester holding a sign that said “Coup plotter” as he stepped out of a black vehicle at around 9.30am.

“I don’t want anybody to take their eye off the ball,” he said, the Axios website reported. “We’re taking down the Biden regime every day. I want you guys to stay focused, stay on message. Remember, signal not noise. This is all noise, not signal.”

The 67-year-old was taken into custody, expected to appear in district court in the afternoon.

The former White House chief strategist was indicted on Friday after defying a subpoena from a House committee investigating the deadly attack on the US Capitol on 6 January by Trump supporters seeking to overturn the election.

Bannon faces two counts of criminal contempt: one for refusing to appear for a congressional deposition and the other for refusing to provide documents in response to the committee’s subpoena.

Each count carries between 30 days and a year in jail. The indictment is the first for criminal contempt of Congress in nearly four decades.

Bannon, a former executive chairman of Breitbart News, pushed false conspiracy theories about the 2020 election.

On 5 January he prophesied on his podcast: “All hell is going to break loose tomorrow.”

That evening he was part of a gathering of Trump allies at the Willard hotel in Washington that the House of Representatives committee has called the “war room”.

Bannon refused to cooperate with the committee by citing an assertion of executive privilege by Trump. Legal experts argue that this has little standing given that Bannon was a private citizen at the time of the insurrection. Last month the House voted 229-202 to hold him in contempt.

A second expected witness, the former White House chief of staff Mark Meadows, defied his own subpoena from the committee on Friday. Trump has also intensified his legal battles to withhold documents and testimony about the insurrection.