Three adults were hospitalized in critical condition and a dog was rescued after a car left running filled a Maryland home with carbon monoxide. Someone forgot to turn off a car left in a garage Friday night attached to a house on Planters Court in Lexington Park, rescuers say. Carbon monoxide leaked through the home overnight. St. Mary's Fire and EMS were called about 7:40 a.m. Saturday to help an unconscious patient. When firefighters arrived, they found three adults going in and out of consciousness from carbon monoxide poisoning. A Maryland State Police helicopter flew them to hospitals in critical condition. A dog inside the home was rescued and is doing fine, authorities say. Firefighters found the car running in the garage. Authorities haven't given an update on the poisoned individuals' conditions.