State police say a crash on I-95 in Augusta that claimed the lives of two motorcyclists occurred after one of the bikers veered into the path of a pickup truck in the passing lane.

Jamie Gross, 58, of Belmont was traveling northbound when his bike veered into the passing lane Sunday afternoon, Maine State Police said Thursday.

The collision set off a chain-reaction crash involving the pickup and several other motorcycles.

Police said the operator of the truck, William Nusom, 67, of Hollis, attempted to avoid the collision by steering his truck into the median guardrail.

The truck then lost control and traveled across the three northbound lanes, striking several bikes before overturning on its side.

Gross and a second motorcyclist, Aaron White-Sevigny, 25, of Windsor, were killed in the accident.

Troopers say the investigation is ongoing and they're trying to determine why Gross veered into the other lane.

The investigation is expected to take several weeks to complete.

The bikers were taking part in the United Bikers of Maine Toy Run.