Two ex-convicts accused of robbing a Family Dollar Store in Biddeford last year by using a rifle to threaten the store clerk were charged with felonies.

The accused gunman, Charles Reed III, 40, appeared in U.S. District Court in Portland on Thursday and pleaded guilty to robbery and gun charges rather than have the case against him presented to a grand jury.

The accused getaway driver, Walter Heathcote, 25, was indicted on two charges last week and pleaded not guilty on Friday.

A third man, described in court documents only as “Male Robber #2,” has yet to be charged in the robbery on Dec. 2.

Reed had a .22-caliber Marlin Model 60 rifle when he and “Male Robber #2″ went into the store, used the gun to take $600 from the clerk and fled in a vehicle Heathcote was waiting in outside, according to court records.

All three men are described in court documents as drug addicts and roommates, though records do not indicate where they lived.

Reed is scheduled to be sentenced Nov. 25. He faces up to 20 years in prison on the robbery charge. He faces seven years to life in prison for a charge of using a firearm during a violent crime. He faces 15 years to life in prison on a charge of possession of a firearm by a convicted armed career criminal. Reed has been convicted of drug trafficking twice and robbery once.

Heathcote, if he is convicted, will face up to 20 years in prison on a charge of aiding and abetting robbery, and 15 years to life in prison for being a felon in possession of a firearm. Heathcote has been convicted of felony robbery five times in Maine’s state courts, according to federal records.

Assistant U.S. Attorney Darcie McElwee did not return a phone call about the status of the case against the third man accused in the robbery.