During the search for survivors and victims, rescuers found an additional 500 pounds (230 kg) of dynamite which had failed to detonate in the south wing of the school. The search was halted to allow the Michigan State Police to disarm the devices, and they found an alarm clock timed to go off at 8:45 a.m. Investigators speculated that the initial explosion may have caused a short circuit in the second set of bombs, preventing them from detonating. They searched the building and then returned to the recovery work.