UVALDE, Texas — A gunman murdered 19 children and two teachers in the deadliest U.S. school shooting for nearly a decade, prompting President Joe Biden to urge Americans to confront the country’s gun lobby and pressure Congress to tighten gun laws.

Authorities said Salvador Ramos, 18, on Tuesday shot his grandmother, who survived, before fleeing and crashing his car near Robb Elementary School in Uvalde, Texas, and killing at least 21 people before being killed, apparently shot by police.