DANVILLE —A bomb threat emptied out Danville Area High School on Monday and led to an early dismissal.

Students were led out of the building to the athletic fields around 12:15 p.m., school officials said. They waited in the fields for about a half hour while officers searched the school, until district officials decided to have school buses pick up students, said Acting Superintendent Ricki Boyle. 

At the same time, parents began arriving in their own vehicles to pick up their children, and ended up waiting in a long line of stalled traffic that backed up onto Route 11. Parents were asked to sign out their students at the high school office.

The district canceled all after-school events such as practices or games that were planned Monday night.

But Boyle expected that students would return to the classroom Tuesday following their normal schedule. 

Everyday, there's "an abundance of security" at the high school, she said. She said she wanted to reassure parents the school was safe. 

Boyle said she could not say much more about the results of the sweep through the school by police officers, because it was an ongoing investigation.