A former White House aide's stunning testimony before the House panel investigating the Capitol attack indicated that the U.S. Secret Service may have had advanced warning of the potential for violence at the Capitol, raising new questions about the agency's planning ahead of the riot and actions taken by agents on Jan. 6.

Cassidy Hutchinson, a top deputy to then-White House Chief of Staff Mark Meadows, told lawmakers on Tuesday that the security team guarding then-President Donald Trump and senior White House officials were aware there was a serious threat posed by some descending on Washington, D.C., on Jan. 6, when Trump was planning to address a rally to support his baseless accusations that the 2020 presidential election was stolen from him.

In Hutchinson's telling, the agency famous for its teams of bodyguards, sharpshooters and hyper-skilled drivers was aware that among the throngs headed to Washington were some who were planning to carry a variety of weapons and military gear, and were seeking to target members of Congress and breach the Capitol building.