The lockdown had been lifted by the time Upper Saucon Township police released details about the incident around 5 p.m.
Officers were called to the crash with injuries on Route 378 in the area of Preston Lane just after 8:35 a.m., police said.
The offending driver fled the scene in their vehicle, abandoning it at the Southern Lehigh Intermediate School, according to township police.
"In an abundance of caution police requested that the district lock down school buildings while officers searched the area," a release states.
After an investigation led police to believe the suspect was no longer in the area, they recommended that normal activities resumed in the early afternoon.
The school district, which is comprised of five schools, also posted an updated notice on its website.
Police say the investigation remains under investigation and are asking any witnesses to contact the department at 610-282-3064.
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