GREGG COUNTY — A Smith County man has been killed when he was hit by a tractor-trailer on Interstate 20. The victim is identified as Humberto Antonio Douglas, 26, of Tyler. The accident occurred near mile marker 594 just west of the Longview city limits around just before 10:15 Friday night. The man was not carrying any identification when he stepped in front of the tractor-trailer. Texas Department of Public Safety troopers worked the wreck.