A 46-year-old Massachusetts woman was seriously injured Thursday morning when her snowmobile crashed and landed on top of her, between Jackman and Rockwood.

The woman, Bonnie Sancomb of Hopkinton, Mass., was on a trail with a group of six snowmobilers when she missed a turn and shot into trees on her sled in Thorndike Township, according to a news release from Maine Warden Service Cpl. John MacDonald.

It appeared speed and unfamiliarity with the trail may have been contributing factors in the crash, according to MacDonald, who said the investigation is ongoing.

MacDonald said when other members of the party realized Sancomb was missing they doubled back and found her 30 minutes later.

The 2012 Arctic Cat Pro Cross F800 snowmobile, which was on its side with its studded track still spinning, was on top of Sancomb, MacDonald said.

A member of the snowmobile party called 911 on a cellphone at 10:35 a.m., and a LifeFlight helicopter from Bangor arrived in Thorndike Township about 11:05 a.m., MacDonald said.

Jackman emergency personnel and Game Wardens John Lonergan, Paul Mason and Troy Dauphinee also responded, MacDonald said.

Bill Jarvis, fire chief for Jackman-Moose River, said frost heaves, potholes, slush and mud slowed emergency personnel responding to the accident.

Sancomb was take by a LifeFlight helicopter to Eastern Maine Medical Center in Bangor, MacDonald said.

The snowmobilers, who were residents of Massachusetts and Connecticut, reportedly left Jackman earlier Thursday morning and were traveling on trail Route 66, also known as Brassua 2 Road.

MacDonald described the trail as groomed and well-traveled.

Jarvis said the trail follows an old logging road and is at least nine feet wide.

The Maine Warden Service advised snowmobilers that conditions vary greatly and urged sledders to slow down and be aware of what lies ahead on the trail.

No information about Sancomb from Eastern Maine Medical Center was available Friday.

Beth Staples — 861-9252

bstaples@centralmaine.com