Two people from the Twin Cities have been charged in South Dakota with hauling 85 pounds of marijuana back to Minnesota in a pickup truck.

Songying Lao, 50, of Minneapolis, and Yia Yang, 41, of St. Paul, were traveling east on Interstate 90 Thursday when a Pennington County sheriff’s deputy pulled them over for speeding, the Sheriff’s Office said Friday.

“During the traffic stop, the deputy noted the smell of marijuana,” the Sheriff’s Office statement read. “Further investigation and search of the Toyota Tundra pickup turned up roughly 85 pounds of marijuana.”

Online records say they remained jailed Sunday in lieu of $100,000 bail apiece following initial court appearances Friday. They are both are due back in court April 20. 

In late January, a routine stop of a truck for a minor driving infraction along Interstate 94 in eastern North Dakota turned up 476 pounds of marijuana worth more than $3 million. Several days later, Minnesota state troopers pulled over a motorist along I-94 in Otter Tail County, and a drug-sniffing dog discovered 200 pounds of marijuana valued at more than $600,000.

In 2017, Minnesota troopers seized more than 2,600 pounds of marijuana — more than six times what they found the year before. Across the border, North Dakota troopers confiscated 300 pounds in 2017, up 88 percent from 2016. One-third of North Dakota’s drug arrests were made along I-94, authorities say. And in Wisconsin, troopers saw a 20 percent increase in drug arrests, mostly marijuana-related, from 2016 to 2017.

Authorities say they think more residents in the three states are buying marijuana where it’s legal, then bringing it back home to distribute.