GRAY – A Good Samaritan helped state police track down a drunken driver, who hit two other vehicles on the Maine Turnpike prior to being arrested tonight at his ex-girlfriend’s house.

Trooper Anthony Keim said 31-year-old William Barbaria of South Portland faces charges of operating under the influence, reckless conduct with a motor vehicle, and leaving the scene of an accident with personal injury.

He was being held at the Cumberland County Jail on $2,500 cash bail.

Keim said a woman from Turner – he declined to identify her – followed Barbaria to his ex-girlfriend’s home on Whitney Road in Gray after Barbaria collided with a pickup truck and another vehicle in the northbound lane of the Maine Turnpike around 6 p.m.

Barbaria allegedly smashed into a pickup truck operated by Kyle Turmelle, 25, of Gray, sending the truck over a guardrail and down an embankment. Turmelle was taken to Central Maine Medical Center complaining of back pain.

Barbaria also rear-ended another vehicle, but the woman who was driving that car did not require medical treatment.

The witness who followed Barbaria communicated with the state police dispatcher by cellphone during the ordeal. When state police arrived at the Whitney Road home, Barbaria surrendered without incident.