A Nevada man has been charged in the fatal shooting of a 16-year-old McDonald’s employee who was killed Sunday night while working the restaurant’s drive-thru window, according to news reports.

On Monday, deputies arrested 24-year-old Justin Michael Mullis of Winnemucca, according to a statement on Facebook by the Elko Police Department.

He remains in custody without bail, charged with murder in the death of Kylee Leniz, the Elko Daily Free Press reported.

Authorities said the attack was random and unprovoked, and that Mullis and the victim did not know each other.

Mullis is accused of walking up to the Elko restaurant in northeast Nevada on Sunday night, approaching the drive-thru window and opening fire on the unsuspecting teenager who died at the scene.

The suspect fled but turned himself in the next day at the police station, where an acquaintance drove him, reports said.

Police did not provide further details about the circumstances of the crime nor about the weapon that was used.

Leniz attended Elko High School, which confirmed the student’s death in a Facebook post on Monday.

Mourners have been leaving flowers, balloons and other tributes at a makeshift memorial outside the restaurant, the Elko Daily Free Press reported.

“It is with a heavy heart that we lost one of our Elko employees and are deeply saddened by the tragedy that occurred last night,” said Chris Kassity, the owner-operator of the Elko McDonald’s, according to NBC. “Our thoughts and prayers are with the family of the employee during this deeply difficult time.”

The investigation is ongoing.