GRAY COUNTY, Kan. (KAKE) - A New Mexico man has died after hitting a semi tractor head-on in southwest Kansas.

The Kansas Highway Patrol says the crash took place just before 9 p.m. Saturday when 44-year-old Alegandro Santiago was driving west on U.S. 50 and crossed into oncoming traffic. He crashed head-on into a semi tractor heading east. The driver of the semi tractor had no apparent injuries but Santiago was pronounced dead at the scene. 

The investigation is ongoing and authorities don't know what caused Santiago to cross into oncoming traffic.