Grapevine death: Big rig driver found dead on 5 Freeway

GORMAN, Calif -- A driver was found dead inside a big rig Thursday morning on the 5 Freeway through the Grapevine, according to the California Highway Patrol.

Authorities say the driver, who has not been identified, was found unresponsive just before 8:30 a.m. Shortly after, he was pronounced dead at the scene.

A cause of death was not yet been announced.

The 5 Freeway was shut down Wednesday night after a major winter storm brought heavy snowfall to the region. It is unclear when the busy thoroughfare will reopen.

DEVELOPING: This report will be updated as more information becomes available.