Police said a raid on Sunday near Drumheller, Alta. turned up a huge marijuana growing operation contained in 10 greenhouses. (Alberta Law Enforcement Response Teams)Police have dismantled a multi-million dollar marijuana growing operation that sprawled over 10 greenhouses on a rural southern Alberta property, officials said Tuesday.

Members of the Alberta Law Enforcement Response Teams (ALERT) raided the property north of Drumheller at about 2 a.m. on Sunday.

Investigators found 3,854 marijuana plants with an estimated street value of $4.8-million, making this the biggest bust of its kind in Alberta this year, officials said.

"Despite its size, this grow operation was fairly low tech," said ALERT's Sgt. Jason Graham.

"In Alberta, most grows are found indoors and supported by sophisticated lighting systems and stolen electricity and water. This one relied solely on the sun and a garden hose."

If the plants had reached maturity — in about one or two more weeks — they could have produced nearly two million marijuana joints, police said.

Nobody was found at the property during the raid. The investigation is still continuing.

Drumheller RCMP first became aware of the grow operation after getting a tip from the public.

ALERT is a provincial organization — comprised of municipal police, RCMP and sheriffs — set up to tackle serious and organized crime.