A Contra Costa County city is home to one of the largest concentrations of illegal marijuana grow houses in the entire state, investigators said.

The California Department of Cannabis Control has raided more than 60 homes in Antioch that have been converted into weed cultivation sites. 

Officials said homes have been literally packed with illegal pot plants.

“The homes, most of them are completely converted to a marijuana grow,” Lieutenant Desmond Bittner of the Antioch Police Department. “Sometimes they may leave a bedroom or two available for whoever’s maintaining the grow for them to sleep in, but as I mentioned, the majority of the home is completely converted into a grow.” 

He said cracking down on the illegal operations has been tough for the city’s resource-strapped department, but now the state department of cannabis control is taking the lead. 

Kevin McInerney of the California Department of Cannabis Control said at least 100 to 200 homes in Antioch are marijuana grow homes. 

Investigators said the marijuana houses are highly dangerous — filled with chemicals, wiring and sometimes standing water.

“When they bypass the electrical meter, there’s a large chance there could be a fire. They do not modify things to code so it’s extremely dangerous,” McInerney said. 

He said one of the recent houses raided belonged to an Oakland police officer and he said nearly all of the houses have been linked to Chinese organized crime. 

“Nearly all of these grows that we’ve served search warrants on in the Antioch and East Bay area are run by Chinese organized crime or run by Chinese organized crime,” McInerney said.

“If you can buy a home for $700,000 and keep it a secret,and do your operations, that’s less than you would get for a huge manufacturing facility,” said Antioch Mayor Lamar Hernandez-Thorpe.

Hernandez-Thorpe believes Antioch is attractive to the criminals because of affordability. He says there were three grow houses near his own home at one time, and is urging Antioch residents to report suspicious activity. 

“If you don’t see your neighbors for a long, long time and you see a van pull up at night time. I think people are pretty keen that something normal is not taking place,” he said.

Investigators said once they’ve uncovered the grow homes, the owners have quickly flipped them selling them for a profit before moving on to new neighborhoods.

The Oakland Police Department released the following statement concerning the allegations on Monday night:

“The Oakland Police Department (OPD) is aware of the allegations made against one of our members and is cooperating with outside law enforcement agencies on the case. The employee in question was placed on administrative leave effective April 30, 2024, and the matter is under investigation. This is an ongoing personnel matter. OPD is unable to provide further details at this time.”