Four people were injured about 11:30 p.m. Friday when the car they were in left the White School Road in Corinth and struck several trees, the Penobscot County Sheriff said early Saturday in a post on its Facebook page.

Three of the four occupants, who have not yet been identified but who are all under the age of 21, were found trapped inside the car, the post said. One was sent by helicopter to Eastern Maine Medical Center with life threatening injuries.

Two were transported by ambulance to the hospital with serious injuries and the fourth was treated for minor injuries, the sheriff’s office said.

Speed and alcohol were factors in the crash, the post said.

Deputies are reconstructing and mapping the crash scene. The road was closed for more than four hours but reopened at 4 a.m. Saturday.

A man, unrelated to the victims, was arrested and charged with disorderly conduct, the post said. He allegedly arrived after the crash and interfered with law enforcement.

Watch for updates.

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