An off-duty Hillsborough County Sheriff's deputy died when a pickup truck he was driving and a flatbed tractor-trailer truck crashed on U.S. 301 Thursday morning.The Florida Highway Patrol said the F-150 collided with the tractor-trailer south of McIntosh Road. The deputy, Derell Brown, 40, driving the pickup, died at the scene from their injuries.Hillsborough County Sheriff Chad Chronister said Deputy Brown was on his way from his shift when he crossed into the other lane and into the path of the tractor-trailer truck.Sheriff Chronister said the truck driver did everything they could to avoid the crash but could not do so."The energy of this truck striking the deputy's personal vehicle, almost head-on, propelled him in a circular motion," Chronister said. "His (the deputy's) car came to rest almost 100 yards north of where the tractor-trailer came to rest."Chronister said Deputy Brown was killed instantly in the crash. FHP said the driver of the tractor-trailer truck suffered non-life-threatening injuries.All lanes of U.S. 301 have been closed for the investigation, and motorists should seek alternate routes if they need to get through the area.Chronister said Deputy Brown was married and had a blended family with five children ages 5 to 20. He had worked with the Sheriff's office for 10 years.