HOLDEN, Maine — The tractor trailer driver involved in Thursday’s fatal crash on Route 1A saw the vehicle cross the centerline and tried to get out of the way, police said.

“It was not a head-on as I reported yesterday. The car actually stuck the rear axle area of the tractor trailer,” Holden Police Chief Chris Greeley said early Friday. “It struck with such devastating force that the car actually spun around and struck a third vehicle.”

[MORE: Orland man killed in crash on Route 1A in Holden]

Derick Warren, 30, of Orland died at the scene after he drifted across the centerline at about 4:45 p.m. near Maine Military Supply and struck the back end of the big rig, driven by Queta Heard, 39, of Georgia, driving for BAB Express LLC, police said.

Why he crossed the centerline is the main question of the investigation, Greeley said.

“It could be anything,” the police chief said. “I cannot say for sure.”

Whether Warren had a health issue, fell asleep or was texting are among the questions Greeley said he hopes the results of his autopsy and the accident reconstruction report will reveal.

Neither the truck driver nor the driver of the third vehicle involved were injured, Greeley said.

Route 1A was shut down until about 8 p.m. so the Maine State Police accident reconstruction team could do its work, Greeley said.