A month-long investigation in Hayward ended Thursday with millions of dollars of drugs off the streets and 13 people in police custody.
Law enforcement seized 1,750 marijuana plants with an estimated street value of $4 million from 11 of the 13 residences searched, according to authorities.
Hayward police narcotic detectives, the Alameda County Narcotic Task Force, the Drug Enforcement Administration and San Leandro police served search warrants at 13 residences -- all allegedly connected to a pot-growing ring -- on Thursday in Hayward, San Lorenzo and San Leandro.
"This happened to be a pretty significant grow," said Sgt. Mark Ormsby of Hayward Police department.
Authorities said in all 11 homes at least two rooms will filled with maturing pot plants ranging in size form 3 to 5 feet.
Bypassed meters were discovered at the locations, indicating theft of electrical power, officers said.
Ormsby said it appears that all of cases were interrelated. One of officers biggest concerns is that the grow houses are popping up more and more in neighborhoods.
"A lot of time times we'd find these industrial grows out in the industrial areas," said Ormsby. In this particular case, all of these were in homes."
Thirteen suspects were taken into custody on suspicion of marijuana cultivation, possession of marijuana for the purpose of sales and theft of utility services.
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