Bismarck police are asking for the public's assistance in locating a teen who ran away two weeks ago.

Benjamin D. Greff, 17, left a treatment facility in Bismarck on Oct. 10, his mother, Beth Greff, said. He has not been seen since.

"Concerns for his welfare are heightened by an existing medical condition that places his health and well-being at risk," a release from the Bismarck Police Department said.

Lt. Mike Arnold, who heads up the department's Police Youth Bureau, said the department rarely asks for the public's help in runaway cases, but Greff has been missing longer than most runaways. Sgt. Dwight Offerman said about two runaways per year are missing for more than a few days.

Greff is 5-feet-8-inches tall, 135 pounds, with brown hair and blue eyes.

Beth Greff said her son gave himself a bluish-black tattoo on his left hand of a stick person holding an umbrella. She said he also has gauged his ears in the past, but the holes in his ears were healing the last time she saw him.

Anyone with information about his whereabouts should call the Bismarck Police Department at 223-1212 or Bismarck Area Crime Stoppers at 224-TIPS (224-8477).

- Jenny Michael