The suspect, 22, was arrested in southwestern Utah after a friend had contacted the authorities, officials said.

© Loren Elliott for The New York Times

The impact of the deaths of Fletcher Merkel, 8, and Harper Moyski, 10, and the injuries sustained by 18 others are only beginning to be felt.

© Mark Vancleave/Associated Press

As students arrive on campus for fall classes, several universities have locked down their campuses after reports of mass shootings that turned out to be false.

© Matt Slocum/Associated Press