WASHINGTON (NewsNation) — The House select committee investigating the Jan. 6 riot at the U.S. Capitol heard from a top aide in former President Donald Trump’s White House Tuesday.

Cassidy Hutchinson, who testified at the surprise hearing, is considered as a vital witness in the sweeping investigation into the Jan. 6, 2021 attack..

Hutchinson, a special assistant and aide to Trump’s chief of staff, Mark Meadows, already provided a trove of information to the committee and its investigators and sat for multiple interviews behind closed doors.

The House panel has not explained why it abruptly scheduled the 1 p.m. hearing as lawmakers were away from Washington on a two-week recess. The committee had said last week that there would be no more hearings until July. This is the fifth televised public hearing investigating the insurrection at the Capitol.

For prior coverage of previous hearings, click here

The Associated Press contributed to this report.