Big Island police identified the 39-year-old man who died after being hit by an 18-wheel semi-trailer truck early Monday morning as Zachary L. Williams, of Honokaa.

Williams was hit on the Hawaii Belt Road about a half mile west of the 38-mile marker near Honokaa between Mailbox Road and Kalopa Road.

Police said a 54-year-old Hilo man driving a 2009 Peterbuilt tractor-trailer west on Highway 19 struck Williams, who stepped out into the roadway at 1:49 a.m.

Williams  was taken to Hilo Medical Center, where he was pronounced dead at 7:10 a.m. The driver of the tractor-trailer was not injured.

Police said the accident happened in a rural area with no fixed lighting. There was no fog or rain at the time of the accident.

Police opened a negligent homicide investigation and have ordered an autopsy to determine the exact cause of death. 

Traffic investigators do not believe that speed, alcohol or drugs were factors with the driver of the tractor-trailer.