The driver of a box truck has been charged with the deaths of three highway workers who were assisting with a lane closure as part of guard rail repair work on Interstate 40 near Statesville, N.C.

The incident occurred in the early morning hours of February 27 along the interstate’s westbound lanes near mile marker 157. According to the N.C. State Highway Patrol, the three workers were reportedly standing between two parked construction vehicles, one of which was equipped with a flashing lights and an illuminated arrow board indicating a lane closure.

Logan Lee Casey, 27, of Cary, N.C., was driving the box truck when it struck one of the parked vehicles at speed. The impact pinned the three workers against the other parked vehicle, killing them instantly.

The victims were identified as Noah Logan Hamilton, 22, of Bonaire, Ga.; Austin Milton, 21, of Jesup, Ga.; and Dustin Gelinas, 20, also of Jesup. All were employees Hazelton, Pa.-based DBI Services, Inc.

Casey, who suffered minor injuries in the crash, has been charged with three counts of misdemeanor death by vehicle. Investigators have yet to determine why the crash occurred, though alcohol has been ruled out as a factor. In addition to the warning indicators on the construction vehicle, signs alerting motorists to lane closure were also in place along the highway, police say.