A head-on two-vehicle collision on the Parks Highway just south of Willow killed one and injured three Thursday.

Alaska State Troopers spokeswoman Megan Peters said troopers were notified at 1:15 p.m. that a sedan and van had collided near mile marker 63 of the highway. Injuries were "very, very serious," she said.

Peters said there are four occupants between the two vehicles.

One lane of the highway is open but traffic is slow going, Peters said.

Troopers are on scene investigating the incident.

The people involved have not yet been identified.

Reach Michelle Theriault Boots at mtheriault@adn.com or 257-4344.