GORHAM — A Dayton woman was killed Thursday morning when the van she was driving was struck by a dump truck, according to police.

Marjorie Mullett, 68, was traveling westbound on Route 25 when a Gorham Sand and Gravel dump truck operated by Ronald Pratt, 59, of Gray swerved to avoid a stopped pickup, according to Gorham police Lt. Chris Sanborn.

The pickup was waiting to turn into Brandy Brook Quarry when the dump truck came upon it, Sanborn said.

After attempting to avoid the pickup, Pratt’s truck struck Mullett’s van before rolling over onto the driver’s side of the vehicle, the lieutenant said.

Mullett was pronounced dead at the scene while her passenger, Gail Lavoie, 58, of Brownfield, suffered non life-threatening injuries and was transported to Maine Medical Center, along with Pratt.

The accident occurred shortly after 9 a.m. and remains under investigation. State police and Gorham police are reconstructing the crash.