THORNDIKE -- A Rhode Island man was in critical condition Monday after he was injured late Sunday afternoon when his all-terrain vehicle flipped and rolled over him.

John Sylvia, 46, and his son were riding ATVs on the gravel section of the Palmer Road, said according to Maine State Police Trooper Tom Welch, who investigated the accident.

Welch said the incident occurred around 5 p.m. after the two had been riding the machines for most of the day.

Welch said Sylvia was turning off Palmer Road and onto the lawn section of his property.

"He began to make the turn when he lost control of the ATV and it rolled over and landed on him," Welch said.

He said Sylvia sustained serious head injuries and was flown to Eastern Maine Medical Center.

"Sylvia was not wearing a helmet," Welch said.

A spokesman at the hospital on Monday said Sylvia remained in critical condition.

Welch said the ATV might have been going too fast for the turn.

The ATV was damaged.