DENVER – A semitrailer was struck by two vehicles in back-to-back crashes in northeastern Colorado and the drivers of both vehicles were killed, the Colorado State Patrol said.

The semitrailer was northbound south of Greeley at 1:20 a.m. Saturday when a southbound pickup truck crossed the center line and struck the semi head-on, killing a 27-year-old man from Keenesberg who was driving the pickup.

Six minutes later, a northbound vehicle ran into the back of the stopped semi, killing the 30-year-old woman who was driving. The 67-year-old Greeley man who was driving the semi was not injured.

Intoxicants are being investigated as factors in the crashes, Trooper Gary Cutler told The Denver Post.