A tractor-trailer traveling in the westbound lanes struck a stationary motorcycle and its rider on the side of the road at mile marker 49.9 in Upper Macungie around 1:20 p.m. on Thursday, Sept. 1, Pennsylvania State Police said.
The impact pushed the motorcycle into another rider, who was standing nearby, police said.
The motorcyclist was taken to Lehigh Valley Hospital-Cedar Crest with serious injuries, while the second victim suffered minor injuries, authorities said.
The tractor-trailer driver was not injured.
The crash caused several hours of delays and detours on the highway.
Anyone with information on the crash or who may have witnessed this crash is asked to contact the Pennsylvania State Police Fogelsville Station at (610) 395-1438.
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