Authorities in Oregon say that a former truck driver pleaded guilty to more than a dozen charges related to a string of interstate shootings that occurred last year.

On Tuesday, former UPS truck driver Kenneth Ayers, 49, pleaded guilty to three counts of attempted murder, five counts of unlawful use of a weapon, three counts of reckless endangerment, and several counts of criminal mischief.

Ayers was arrested on August 20, 2020, following an investigation spearheaded by the Oregon State Police into a string of shootings that occurred on I-5 in Douglas, Josephine, and Jackson Counties dating back to May 2020.

Ayers was particularly connected, troopers say, to an August 19 shooting that occurred on I-5 at mile marker 37 in Jackson County that sent a woman to the hospital with a gunshot wound to the shoulder.

During the course of the investigation into the serial shootings, Oregon State Police began to suspect that a UPS truck was involved.

Soon after the August 19 shooting, troopers were reportedly able to locate a UPS truck approximately 60 miles north of the shooting site and executed a search warrant on the truck and trailer driven by Ayers.

Ayers was arrested after troopers found a firearm consistent with the type used in the I-5 shootings in his truck.

UPS has issued the following statement on the shootings: “We are appalled to hear about these allegations and are fully cooperating with the responding authorities. Firearms are prohibited at UPS facilities and in our vehicles. We are extremely concerned for the motorists and other individuals who have been affected.”

Authorities have not disclosed any motive for the string of shootings.

Ayers is scheduled for sentencing on March 2, 2021.