A 19-year-old found unconscious and unresponsive on Ridge Road early Thursday morning died of a suspected drug overdose.

Andrew Martin Mannix, who lived in Damascus and Frederick, was found unconscious shortly after 8 a.m. along the side of Ridge Road. He was with an old friend, Brian Harris, 18, of Damascus.

The two had been upset and swallowed pills the night before, Harris told The Gazette. They had passed out in the tall grass along Ridge Road in the early morning hours, he said.

When Harris awoke, the sun was up and he tried to wake his friend. When he checked for a pulse and could not find one, he ran to a nearby house and told the owner to call for help, he said.

Harris, who had been a fire department volunteer, went back to his friend and started cardio pulmonary resuscitation until police and fire and rescue officers arrived.

Mannix was transported to Shady Grove Adventist where he died.

County police spokeswoman Lucille Baur said an autopsy will be performed to officially determine a cause of death, but police believe Mannix died of a drug overdose.

Mannix graduated from Damascus High School this summer. His mother, Debra Fields Brown, lives in Frederick.