Several hundred people were arrested this week in Kentucky raids aimed at traffickers who bring prescription drugs into the state.

Investigators say the violators go out of state to avoid Kentucky's strict prescription tracking system, the Lexington (Ky.) Herald-Leader reported. One popular destination is South Florida, with Kentucky residents traveling to clinics there to get prescriptions for oxycodone and other pain medication that can be resold.

State police said at a news conference Thursday in Lexington a total of 518 people had been charged in the case and more than 300 had been arrested by Thursday afternoon.

Federal, state and local law enforcement joined in the effort.

"There is no higher priority than this prescription drug battle," assistant U.S. Attorney Bob McBride said at the news conference.