Federal prosecutors have charged a man driving from California to Minnesota and arrested in Sundance with possession with intent to distribute more than 300 pounds of marijuana, according to court records.

Cher Yang was charged in a criminal complaint filed last week, according to an affidavit filed in U.S. District Court. The federal government has requested a detention hearing for him.

If convicted, Yang faces up to 20 years of imprisonment and up to a $1 million fine.

The case started on Jan. 22 when Wyoming Highway Patrol Trooper S. Muller made consensual contact with Yang whose rental truck was parked at the Sundance Travel Center, according to the affidavit written by Wyoming Division of Criminal Investigation agent Trevor Budd. Yang's traveling companion was Yeng Vang.

"Throughout the course of Trooper Muller's contact with Yang and Vang, they provided inconsistent answers and unusual plans," Budd wrote. "They also displayed unusual nervousness in their interaction with Trooper Muller."

Muller asked for the help of another trooper and his drug detection dog.

Yang consented to having the trooper walk the dog around the truck, and the dog alerted to the presence of a controlled substance.

"A subsequent search of the vehicle was completed and revealed over 155,350 grams (342.49 pounds) of marijuana in bud form was located," Budd wrote.

The marijuana was concealed in 285 vacuum sealed packages in 15 moving boxes with markings unique to each box, he wrote.

Later that day at the Crook County Detention Center, Budd and another DCI agent interviewed Yang, who waived his Miranda rights and admitted he was knowingly taking the marijuana from California to St. Paul, Minn.

Yang also said he was being paid $20,000 for making the trip. When he arrived in St. Paul, he was to contact an unnamed person and receive instructions where to park the rental truck.

He didn't know how much marijuana he was transporting, but he told agents it was "'a lot,'" according to the affidavit.

The suspected marijuana was sent to the Wyoming State Crime Laboratory and tested positive for the presence of tetrahydrocannabidinol, the primary intoxicant in the drug.