Mt. SAC: Los Angeles Schools Bomb Threat Live Updates: Mt. San Antonio College Campus, Walnut High School Investigations Launched

A bomb threat in Walnut, California, led to the lockdown of Walnut High School and an evacuation at Mt. San Antonio College Thursday. The threatened time for explosions at the Los Angeles-area schools was 2:45 p.m. PDT (5:45 EDT), said school officials. "Calmly leave campus. Classes/services are closed until at least 4:30pm. NOT A DRILL," the school's official account tweeted.