Oak Hills, California - A massive marijuana bust has left cops in California stumped after they found $100 million worth of the drug, neatly bagged up, but without an owner in sight.

Detectives were called to a property in Oak Hills, California, by neighbors who noted a strong smell coming from a newly built warehouse.

Once they got inside, they found the whole 450-square-meter structure stuffed with trash bags full of marijuana.

The 3,000 bags, which weighed a total of 45 tons, took officers two days and 51 truckloads to move.

But just who owns the haul, which has a street value in excess of $100 million, is a mystery.

Detective Chris Bassett of the San Bernardino County Sheriff's Department admitted that officers were stumped by the find.

Asked by a reporter if investigators had any idea who it belonged to, he replied: "Not at this time."

"The first thought that went through my mind is, where is this marijuana going? Is it going to illegal dispensaries? Is it going to be distributed throughout the United States?" he said.

Marijuana – both medicinally and recreationally – is legal in California, but commercial cultivation requires a permit.