Investigators believe they know whose truck a rock fell from on the Sterling Highway Thursday afternoon, fatally striking an 8-year-old boy riding in a passing car, but haven’t yet named the driver.

Jonathon Taylor, a spokesman for the state Department of Public Safety, declined to say Friday whether the vehicle from which the rock fell near Mile 58 of the Sterling Highway was operated by the state or a contractor associated with highway work. Noah Schwebach, 8, was struck and killed at about 1:30 p.m. by what Alaska State Troopers called a “volleyball sized rock” that went through the windshield of the Volkswagen hatchback in which he was riding and struck him.

KTVA viewer Dianna VanNuck, who was near the scene Thursday, said she saw investigators measuring the distance between a rock on the roadside and the rear window of the hatchback Schwebach had been riding in.

Witness Dianna VanNuck took this photo of the rock she believes killed an 8-year-old boy on the Sterling Highway on July 19, 2018. (Credit: Dianna VanNuck)

“We have tentatively identified the truck and the driver, but as that information is not confirmed I cannot relay that information at this time,” Taylor said.

Work in the area where the fatal rock fall occurred, between Mile 58 and Mile 79, has included installing wildlife culverts so moose and other big game can pass under the roadway rather than risking vehicle collisions on the highway.

The state Department of Transportation and Public Facilities issued a statement Friday, saying staff were "saddened and shocked" by Schwebach's death, which occurred in the work area.

"Granite Construction is the contractor performing the work in this area and they are cooperating with the Alaska State Troopers in their investigation," state officials wrote. "This is an active investigation and department staff are providing information to the Alaska State Troopers."

A statement from Granite Construction, which is handling the Sterling project, said employees’ “thoughts and prayers are with the Schwebach family.”

“While the incident occurred within our project site, we are presently unaware that any of our equipment or personnel were involved,” Granite officials wrote. “We are fully cooperating and assisting with the investigation. Out of respect for the family, we have voluntarily suspended night shift work on the roadway until Saturday night.”

Taylor asked anyone with information on the rock fall to contact the Soldotna trooper post at 907-262-4453.

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