BARSTOW An active-duty Army Sgt. First Class as recently as September, Lucas Donahue entered into a plea bargain this week for multiple gun and drug charges and was sentenced to four years in prison, court records show.

Donahue, 32, was arrested last summer with an arsenal of guns and was suspected of targeting law enforcement agencies.

Donahue pleaded guilty to four charges (one of which included a special allegation) in three separate cases Tuesday during a pre-preliminary hearing at Barstow Superior Court.

Donahue is guilty of possession of a controlled substance with a loaded firearm, transportation of a controlled substance, possession of a silencer and possession of a controlled substance for sale, court records show.

For each charge, he was sentenced to two years in prison, with all sentences to run concurrently, according to court records.

Donahue was also sentenced to two years in prison for a special allegation which was part of the charge for possession of a controlled substance with a loaded firearm. That sentence will run consecutive to the others, court records show.

Donahue will have 408 days knocked off the sentences for time served and good behavior.

Last August, Fort Irwin military police found a military-grade armory in Donahue's truck, according to previous reports. The weapons included a black revolver, a semi-automatic handgun with laser site attachment, the barrel of an AK47 assault rifle and several homemade silencers.

Military police also located inside his truck a map of Barstow marked with symbols used in U.S. Army Ranger combat missions.

Believed to be kill zones, the marks three small red circles with a "K" in the middle were placed over locations of the Barstow Police Department, San Bernardino County Sheriff's Department and the California Highway Patrol, according to previous reports.

Over the course of a year, beginning in late 2011, Donahue was arrested at least three times for weapons charges, according to a search warrant affidavit written by Barstow Police.

A search of his Barstow apartment in August of last year after police had obtained a search warrant revealed multiple firearms and combat accessories.

Military officials had told Barstow police detectives Donahue allegedly threatened to kill his company commander by stabbing him in the neck.

A spokesperson at Fort Irwin could not confirm Donahue's official military status as of Wednesday, but a dishonorable discharge was pending last September.

Neither Deputy District Attorney Kris Parde nor Deputy Public Defender Troy Padgett could be reached for comment.

Shea Johnson may be reached at (760) 256-4126 or at SJohnson@DesertDispatch.com.