SPRINGFIELD, Mo. (AP) — Narcotics investigators in Springfield say the city is seeing an influx of higher-grade marijuana from states where the drug is legal, particularly Colorado.

Dan Banasik, a Missouri State Highway Patrol supervising sergeant for narcotics, says the more potent drug has driven up prices for the drug.

The Springfield News-Leader reports a few years ago, undercover narcotics officers could by a pound of marijuana from a dealer for about $1,000. Today, that same undercover operation would cost about $6,000.

Sgt. Shawn Griggs says the patrol seized about 1,071 pounds of marijuana in 2013 and about 1,700 pounds in 2014. The patrol has already seized more than 1,000 pounds halfway through this year.

Griggs says the patrol has also seen a huge increase in marijuana-infused food products, known as edibles.