Four people are dead after a head-on crash Monday morning 15 miles north of Caribou.

A car and a sport utility vehicle collided on Route 161 in an area known as Rainbow Cove in Township 16 Range 4, Maine State Police said. The accident was reported at 10:20 a.m.

Police identified the dead as the driver of the SUV, Kimberly Lausier, 38, of Madawaska, and the three occupants of the sedan, Bobbi-Jo Johnston, 33, of Fort Fairfield, her 2-year-old daughter, Alana Nelson, and the driver’s mother, Laurie Ann Johnston, 52, of Carlingford, New Brunswick.

A passenger in the SUV, Robert Lausier, 53, the husband of the driver, was taken to Cary Medical Center in Caribou, then transferred to Eastern Maine Medical Center in Bangor with serious leg injuries that are not considered life-threatening.

The crash occurred when the driver of the southbound SUV tried to pass a tractor-trailer and hit the northbound sedan, according to Stephen McCausland, spokesman for the Maine Department of Public Safety.

Those killed were pronounced dead at the scene.

Police could not locate the driver of the tractor-trailer, who may not have realized the crash occurred, McCausland said.

Police are asking the truck driver to contact them at 532-5400.

Route 161 was closed for more than seven hours.