Rome police seize marijuana crop in tunnel (VIDEO)

Hundreds of marijuana plants were found growing in the Mussolini-era tunnel.

Italian authorities have made one of their biggest ever marijuana busts after discovering hundreds of plants growing in a Mussolini-era metro tunnel in Rome.

Financial police found the illegal crop, located near the Italian central bank, on Saturday after detecting a strong odor coming from the tunnel during a routine patrol of the area, the New York Times reported.

Inside the one-kilometer-long passageway were rows of marijuana plants growing in rooms lit by halogen lamps and watered by an underground irrigation system, according to the BBC. 

Agence France-Presse said police seized 340 kilograms of the drug with an estimated street value of three million euros ($3.7 million).

The BBC, citing local media reports, said about 900 plants were growing across half a hectare in the tunnel.

Police released video footage of the tunnel. 

A 57-year-old man has been arrested, Reuters reported.

The AFP said the authorities were looking for other suspects.

“We found three or four work coveralls, chemicals that would be used by experts, as well as a blackboard with work shifts marked on it,” Colonel Stefano Corsi of the provincial branch of the financial police was quoted by the New York Times as saying.

“It was a regular business. It was a very sophisticated operation.”

The metro tunnel was built during the rule of fascist dictator Benito Mussolini in the 1930s and abandoned after Italy joined World War Two.

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