WASHINGTON (AP) — The House committee investigating the Jan. 6 attack on the U.S. Capitol issued a subpoena Friday to Donald Trump.

The nine-member panel issued a letter to Trump's lawyers, demanding his testimony under oath by Nov. 14 and outlining a request for a series of corresponding documents, including personal communications between the former president and members of Congress as well as extremist groups.

It is unclear how Trump and his legal team will respond to the subpoena. He could comply or negotiate with the committee, announce he will defy the subpoena or ignore it altogether. He could also go to court and try to stop it.

The subpoena is the latest and most striking escalation in the House committee’s 15-month investigation of the deadly Jan. 6, 2021 insurrection, bringing members of the panel into direct conflict with the man they have investigated from afar through the testimony of aides, allies and associates.

The panel — comprised of seven Democrats and two Republicans — approved the subpoena for Trump in a surprise vote last week. Every member voted in support.

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