A sprinkler alarm brought authorities to a marijuana grow in Graham.
When Pierce County sheriff’s deputies searched the warehouse Dec. 14, they found a 28-year-old man hiding in one of the rooms.
There were 1,600 marijuana plants in various stages of growth spread across six rooms.
The operation was protected by 16 surveillance cameras and two armed men, according to court documents.
Deputies were called to check on the warehouse after a sprinkler system set off an alarm. After finding the pot and evidence that someone was living there, they called in a search dog and found the 28-year-old.
During the investigation, three men drove up and allegedly admitted to knowing about or being involved with the grow.
The 28-year-old was arrested and charged with unlawful manufacture of a controlled substance. He pleaded not guilty in December.
On Monday, prosecutors charged three more men — ages 26, 27 and 32 — with the same charge. They are to be arraigned March 27.
Surveillance footage showed the men practicing drawing and aiming their guns, records show.
Stacia Glenn: 253-597-8653