Several calls went out to parents before 6 a.m. alerting them to a possible bomb threat.
Police and K9 units swept the school's campus for several hours before giving the "all clear."
Officers said they were unable to find a credible threat.
Buses were released to pick up students around 7:45 a.m.; however, school officials said elementary students would be picked up first.
Holly Springs HS is a school bus hub, so hundreds of students who usually ride in the morning must wait until authorities investigating a bomb threat say it’s okay for drivers to arrive here and roll off the campus to start their routes. #abc11 pic.twitter.com/522e8zd0fY— Anthony Wilson (@AnthonyABC11) April 23, 2018