The two Libby men authorities caught flying Spokane-sourced drugs into Lincoln County Airport on Sept. 13 recently signed plea agreements and were scheduled for sentencing, court documents show.

Hugh Shawgo and Michael Norton signed plea agreements on Dec. 13. Both will be sentenced April 5, 2018 in the Russell Smith Courthouse in Missoula — Shawgo at 9 a.m. and Norton at 10 a.m.

Shawgo pleaded guilty to two counts: possession with intent to distribute methamphetamine, and possession of a firearm in furtherance of a drug trafficking crime. If convicted he faces a mandatory minimum sentence of 10 years to life, a $10 million fine, five years of supervised release and a $100 special assessment for the former charge and mandatory minimum and consecutive sentence of five years to life, a $250,000 fine, five years supervised release and a $100 special assessment for the latter charge.

Shawgo also agreed to forfeit a handgun. A charge of conspiracy to distribute methamphetamine will be dismissed if the court accepts his plea at sentencing.

Norton pleaded guilty to possession with intent to distribute methamphetamine. If convicted he faces a mandatory minimum sentence of 10 years to life, a $10 million fine, five years of supervised release and a $100 special assessment.

Norton also agreed to forfeit an airplane, rifle with high-capacity magazine and a 1999 Chevrolet Corvette. Charges of conspiracy to distribute methamphetamine and operating as an airman without an airman’s certificate will be dismissed if the court accepts his plea at sentencing.

Both men’s guilty pleas are unconditional.

According to a criminal complaint prepared by Troy Casper, a special agent with the Department of Homeland Security, the Northwest Montana Drug Task Force and the Lake County Sheriff’s Office in August began investigating Shawgo for distributing methamphetamine in Western Montana. Shawgo at the time was under probation and parole supervision for a September 2015 felony conviction of operating an unlawful clandestine lab, and has at least three prior felony convictions for drug possession in Washington and Idaho.

About 4 p.m. on Sept. 13, Lincoln County Sheriff’s Detectives Nate Scofield and Brad Dodson saw Shawgo driving toward the Lincoln County Airport to, they believed from prior knowledge, fly to the Spokane area to pick up drugs and bring them back to Libby.

At about 4:45 p.m. and 7 p.m., Dodson listened to two recorded phone calls between Shawgo and a woman in Lincoln County Jail. In the first call Shawgo said they had landed in the Spokane area and were driving to the area of Airway Heights; in the second call Shawgo said he was driving “with a big ball of brown (heroin) in his hand” and that they needed “to fly out soon to get back before dark.”

At 8:15 p.m., the detectives and other agents watched a plane registered to Norton land at Lincoln County Airport. They arrested the plane’s occupants, Shawgo and Norton, without incident. After obtaining a search warrant authorities found on the plane heroin, methamphetamine, assorted prescription medication, a pistol and $906 in cash.

Investigators found that Norton twice had been arrested and once was convicted for felony criminal possession of dangerous drugs.