The Iowa County Sheriff’s Office said the shooting was reported shortly before 3 a.m. and that when officers arrived, they found the trucker dead from apparent gunshot wounds in the cab of his tractor-trailer.

This Wednesday, Sept. 6, 2017 booking photo released by the Iowa County Sheriff’s Department shows Mariana Lesnic, in Marengo, Iowa, who is charged with first-degree murder in the shooting of a truck driver found dead in his cab at a rest stop early Wednesday, along Interstate 80 near Victor, Iowa. (Iowa County Sheriff’s Department via AP)

Mariana T. Lesnic, 43, was found at the scene and taken into custody. She was charged with first-degree murder and was being held at the Iowa County jail in Marengo on a $1 million cash-only bond.

In a criminal complaint, investigators allege that Lesnic killed the victim “willfully, deliberately and with premeditation by shooting him with a firearm” but provided no additional details. Authorities were withholding the victim’s name pending notification of his relatives.

The sheriff’s office said Lesnic’s address was unknown. The criminal complaint indicates that she has a Colorado driver’s license. A first-degree murder conviction in Iowa carries an automatic sentence of life in prison without parole.