A tractor-trailer driver pursued by state troopers before crashing on Interstate 81 near Shippensburg may have been suffering from a medical episode, according to police.
Trooper Robert Hicks said the Chambersburg Barracks was notified of an erratic tractor-trailer traveling northbound near mile marker 17 Wednesday afternoon.
He said troopers pursued the semi until it crashed in the median just north of the King Street Exit in Southampton Township.
The truck struck the Goodhart Road underpass and came to rest with its front wheels dangling over the retaining wall.
The driver, who was not identified, was taken to Chambersburg hospital as a precaution.
The crash slowed traffic on Interstate 81 during the evening commute.
No other vehicles were involved in the crash.