RACINE, Wis. - Authorities say nearly a ton of marijuana with a street value of more than $7 million was discovered in a pole barn in Racine County and confiscated.

A dump truck was needed to haul away the marijuana, found in the attic of a barn near Raymond Monday. Racine County Sheriff Christopher Schmaling says the elaborate growing operation had a specialized furnace system to heat and cool the marijuana.

Officials say an anonymous tip to Greenfield police led deputies to the operation. Authorities tell WTMJ-TV the 44-year-old suspect was armed when he was arrested.

Schmaling says the bust, which netted 1,800 pound of marijuana, is the largest of its kind in Racine County.