Israel Police said on Tuesday that they uncovered what they called "one of the largest" illegal drug operations ever caught in Israel.
Police said in a statement that a clandestine investigation that began several months ago led them to an underground compound in the central city of Rishon Lezion where the narcotics were being produced.
Officers seized marijuana plants and equipment used for growing and manufacturing drugs worth an estimated NIS 15 million ($4.8 million).
Police arrested seven suspects — all in their 30s and from central Israel — who may face multiple drug trafficking and production charges.
Chief Superintendent Yaniv Wolowitz said he believed that organized crime gangs were behind the marijuana grow-up which he described as "one of the largest and most unique laboratories ever captured in Israel."
"This is an open area in the heart of Rishon Lezion, a seemingly innocent place, and the entire laboratory is located underground," Wolowiz said.
"You walk into a container, go downstairs and then discover a laboratory in which a lot of money has been invested. We have no doubt that criminal organizations are behind its financing. I have no doubt that this drug bust prevented large amounts of drugs from reaching the streets and being distributed at clubs and schools."