Updated

Federal authorities in Southern California have filed three asset-forfeiture lawsuits against properties housing six marijuana stores in the city of Anaheim.

The Los Angeles U.S. attorney's office said Tuesday that warning letters have also been sent to people associated with 66 marijuana operations in Anaheim and the nearby Orange County city of La Habra.

Last October, California's four U.S. attorneys announced a crackdown on medical marijuana operations, saying dealers and suppliers are using the state's medical pot law as legal cover for running sophisticated drug-trafficking ventures in plain sight

The asset-forfeiture lawsuits allege that while the stores purport to be medical marijuana dispensaries operating under California law, such distribution is not an exception to the federal Controlled Substances Act.