ColPARKER, Colo. (AP) _ A high school was evacuated Friday and a student was taken into custody after a small explosion outside the building, but no injuries or damage were reported, authorities said.
Authorities have not said what caused the explosion at Ponderosa High School in Parker, about 15 miles southeast of Denver.
A junior at the school was being questioning about chemicals in a backpack that ``could have been mixed to create another small sound-making device,'' school and sheriff's officials said in a statement.
They did not immediately give more information. Classes were canceled for the day at the school that has 1,958 students, according to state figures.
Other schools around the country investigated possible threats of violence after this week's massacre on the Virginia Tech campus and on the eighth anniversary of the Columbine High School shootings.
A middle school in Lamar, Colo., about 160 miles southeast of Denver, was evacuated after a handwritten threat to blow up the school was discovered.
In Iowa, a community college campus was closed after ``VT Here Today'' was scrawled in marker on a women's restroom stall. Officials with Scott Community College's campus in Bettendorf said they know who made the apparent threat but would not release more information.
On Thursday in Missouri, a community college fired a part-time geography instructor who allegedly joked in class about being a suicide bomber. Police in the town of Ozark said the teacher told them he was trying to lighten students' mood before a test.