A trucker who caused a wreck that killed a highway worker was allegedly watching porn around the time the crash occurred, according to Minnesota authorities.

Tate Doom, 49, was charged with criminal vehicular homicide and criminal vehicular operation this month following an investigation that had been under way since the fatal accident happened in October, Minneapolis radio station WCCO reports.

Doom was behind the wheel of an 18-wheeler that rear-ended a truck and trailer in a work zone on Interstate 94 in the city of Rogers. The trailer broke free and struck and killed construction worker Vernon Hedquist, 59, who was standing on the highway's shoulder.

Rogers is about 25 miles northwest of Minneapolis.

Another worker was injured by flying debris, according to the Minneapolis Star Tribune.

According to WCCO, investigators searched Doom's cellphone and recovered deleted files from PornHub. They believe he played them around the time of the crash, however Doom has denied that.

Doom told investigators he was driving 50 mph before the wreck, but authorities allege he was actually traveling 72 mph. The speed limit in the area is 70 mph, the Star Tribune says.