WASHINGTON (BLOOMBERG) - Former White House chief of staff Mark Meadows and three other of former president Donald Trump's advisers were subpoenaed on Thursday (Sept 23) by the select House committee investigating the Jan 6 insurrection at the US Capitol.

Along with Meadows, subpoenas were sent to former Trump political adviser Steve Bannon, former deputy chief of staff Dan Scavino and former Defence Department official Kashyap Patel.

The subpoenas are the first issued by the committee and they instruct Mr Meadows and Mr Scavino to appear at depositions in Oct 15 and Patel and Bannon, a day earlier, on Oct 14. The subpoenas also demand that they produce documents by Oct 7.

"The Select Committee is investigating the facts, circumstances, and causes of the Jan 6th attack and issues relating to the peaceful transfer of power, in order to identify and evaluate lessons learned and to recommend to the House and its relevant committees corrective laws, policies, procedures, rules, or regulations," committee Chair Bennie Thompson said in letters to the four men.

The subpoenas mark a new phase in the investigation, one that is likely to spark legal battles.

The committee, made up of seven Democrats and two Republicans, had already requested information involving Mr Trump and members of his White House staff.

The National Archives was asked to turn over White House documents provided to Mr Trump or Mr Meadows with terms such as "rigged" election or "stealing" the election.

Mr Thompson, a Mississippi Democrat, has said that in addition to examining how law enforcement and intelligence agencies operated, the panel would look into events at the White House on the day of, and after the riot, which occurred as Congress was meet to certify Mr Joe Biden's victory in the 2020 presidential election.

Members of the committee have made clear that Mr Trump's activities that day are a central focus of their inquiry.

Committee member Adam Schiff, a California Democrat, said on Thursday that the panel might recommend potential criminal prosecution by the Justice Department for "those who willfully and in bad faith resist cooperating, when they're compelled to do so".

The committee has to "anticipate that there are people who don't want to talk - because they feel that would incriminate them or incriminate others," Mr Schiff said.

For instance, Mr Thompson writes to Mr Meadows, "It appears you were with or in the vicinity of President Trump on Jan 6, had communications with the President and others on Jan 6 regarding events at the Capitol, and are a witness regarding activities of that day".

The letter also states that documents provided by the Department of Justice showed he "communicated directly with the highest officials" at the department "requesting investigations into election fraud matters in several states".

Thompson, in his letter to Mr Bannon, says he "has been identified as present at the Willard Hotel on Jan 5th, 2021, during an effort to persuade members of Congress to block the certification of the election the next day".

The letter also states Mr Bannon has been described as communicating with Trump on Dec 30 and other occasions, urging him to plan and focus for Jan 6.

"Moreover, you are quoted as stating on on Jan 5th, 2021, that "(a)ll Hell is going to break loose tomorrow," Mr Thompson writes.

Reached on Thursday night, Mr Ben Williamson, a Meadows spokesman said: "Decline to comment. Will keep you posted."

Mr Bannon did not immediately respond to a request for comment.

Mr Trump, in a statement, derided the committee's "harassment subpoenas" and said: "Hopefully the Unselect Committee will be calling witnesses on the Rigged Presidential Election of 2020, which is the primary reason that hundreds of thousands of people went to Washington DC in the first place."