An autopsy will be done at Western Michigan University to determine the cause of death of a semi truck driver who was killed in a crash on I-94 in New Buffalo. The Berrien County Sheriff’s Department responded just before 9 Friday morning to the wreckage at mile marker 1 along westbound I-94. The semi was fully engulfed in flames when first responders arrived. Witnesses say the truck hit a guardrail before going off the highway and hitting a tree and then it burst into flames. It’s not yet known if the driver had a medical emergency or if a mechanical issue caused the crash. The truck was taking clothing to Meijer stores in Wisconsin. Police say the driver’s name and hometown are being withheld pending notification of his family.