A 50-year-old Montana man died after his tractor-trailer went off Interstate 84 in south-central Idaho and crashed into a concrete support for an overpass.

Idaho State Police say Harold Gow of Missoula died at the scene of the crash that occurred about 5 a.m. Friday near mile marker 205 in Minidoka County.

Police say Gow's 2010 Kenworth semitrailer drifted into the median and struck a guard rail before hitting the support.

The crash is under investigation.