81-year-old dies after being hit by tractor-trailer in Lehigh County, Pa.

UPPER MACUNGIE TWP., Pennsylvania (WPVI) -- An 81-year-old Allentown man was killed Wednesday afternoon after being hit by a tractor-trailer in Lehigh County, Pennsylvania.

It happened around 2:15 p.m. on Route 222 in Upper Macungie Township.

The man was pronounced dead at the scene. He has not been identified.

Authorities are still investigating what caused the crash.

Police said the driver of the tractor-trailer was not physically hurt and is cooperating with investigators.

No other vehicles were involved in the incident.