Four years later, the largest lingering mystery of the Capitol riot remains unsolved.

© Jason Andrew for The New York Times

The attack that left 15 dead and about three dozen injured followed a distressingly familiar pattern of assailants turning vehicles into weapons.

© Edmund D. Fountain for The New York Times

Less than a month ago, New York State authorities charged Luigi Mangione with an act of terrorism in the killing of a health care executive in a shooting in Midtown Manhattan.

© Gerald Herbert/Associated Press

An Islamic State terror group flag was found in the suspect’s vehicle, investigators said, as well as a bomb near the vehicle used in the attack.

© Edmund D. Fountain for The New York Times

Leaders of the big telecommunications companies were summoned to the White House to discuss strategies for overhauling the security of the nation’s telecommunications networks amid growing alarm at the scope of a Chinese hack.

Phones used by Jared Kushner and Eric Trump were among those that hackers sought access to as part of a counterintelligence effort carried out by a hacking group associated with China.

A group that experts call Salt Typhoon is believed to be behind a sophisticated breach of major telecommunication companies that has taken aim at American leaders.

The targeting of the Republican presidential ticket’s phones is part of what appears to be a wide-ranging effort to gather information about American leaders.