The threat was reported about 2:20 p.m. on a bus at the intersection of S. Machias Road and Old Machias Road, according to school and police officials. The bus had just left Centennial Middle School and was about a mile away when a student on the bus reportedly yelled "bomb."
The bus pulled over and was evacuated. Most of the students were put on another bus and taken home about 90 minutes later.
Police detained one student at the scene for questioning, sheriff's spokeswoman Shari Ireton said.
"At this time, it is believed that this was a false threat made by a student on the bus," she said.
The school district posted updates to its website throughout the incident.
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