Rock County sheriff’s deputies seized 2 pounds of marijuana Monday after receiving a tip about a suspicious FedEx package.

The tip about suspected illegal drugs came from the Minneapolis-St. Paul Airport Police, who said the package, sent from California, had a Beloit destination, said Capt. Aaron Burdick of the sheriff’s office detectives.

Deputies used a search warrant and a drug-sniffing dog to check the package at a FedEx facility in Janesville and intercepted it before it could be delivered, Burdick said.

Law enforcement sometimes allows such packages to be delivered to make an arrest, but that was not done in this case for investigative reasons that can’t be revealed at this time, Burdick said.

The marijuana was in sealed plastic bags concealed inside a plastic toolbox, Burdick said. It was described as “high grade.”

Burdick said lower-quality marijuana usually has leaves and stalks, but this was mostly buds, which contain the highest concentrations of THC.

No arrests had been made as of Wednesday afternoon, but the investigation continues, Burdick said.