BILLINGS, Mont. - Robert F. Armstrong, aka Dr. Bob, arrested last week for allegedly bringing large amounts of methamphetamine from Moses Lake to Montana, has a history of drug convictions dating back more than 25 years.

Armstrong, 49, was one of 12 people arrested on drug charges by an interagency partnership, Project Safe Bakken, to crack down on drug trafficking in the thriving Bakken oil patch in Montana. Armstrong is facing federal drug conspiracy charges that carry a potential sentence of 10 years to life in prison if convicted.

At the time of his arrest, Armstrong was wanted by the Washington Department of Corrections for failing to check in with corrections authorities. Armstrong was placed on 12-month community supervision after he was convicted in April of last year for possession of methamphetamine. According to Grant County Superior Court records, Armstrong was found in possession of several plastics bags of methamphetamine following a traffic stop in Moses Lake. He served seven months in jail.

The first drug conviction for Armstrong was in 1987, when he was found guilty of possession of heroin and a machine gun or parts contraband violation, both felonies. He served nine months in Grant County Jail for the convictions.

Armstrong was convicted again in 1998 and 2008 for drug possession, and was sentenced to 90 days in jail.

Armstrong had also been convicted on six gross misdemeanor charges, including possession of a controlled substance and three DUI convictions.

Two other suspects arrested in Montana were also from the Basin. Jaime Alberto Garza, 42, of Othello, and Enrique Lopez Solano, 40, of Warden, was charged with conspiracy to possess methamphetamine with intent to distribute and possession with the intent to distribute methamphetamine.

Armstrong has been charged with drug distribution and possession offenses and possession of a firearm during a drug trafficking crime.

Armstrong and most other defendants in the Montana case pleaded not guilty during initial court appearances last week.