Los Angeles County sheriff's deputies discovered more than 200 pot plants growing inside a home in Temple City.
Two assault weapons and a handgun were also discovered in a residence in Covina. Investigators also searched two homes in Valinda as part of the investigation.
Four suspects were arrested Tuesday in connection with the illegal operation. Three additional suspects were arrested a day later. Officials say the suspects may be affiliated with a Chinese gang.
All seven suspects were booked into the Industry sheriff's station on suspicion of illegal cultivation of marijuana. They were each being held on $50,000 bail.
Anyone with information about this case was asked to contact L.A. Crime Stoppers at (800) 222-TIPS.