HARMONY — A California man was arrested and thousands of marijuana plants were confiscated Tuesday after officials raided another unlicensed growing operation in rural Maine.

The bust occurred at about 10 a.m. at a residence on Cooley Road in Harmony, where officials discovered about 3,400 cannabis plants growing in a detached garage, according to Somerset County Sheriff Dale Lancaster.

The operation was different from the others that have been raided across the county, Lancaster said, because the growing operation was confined to the detached garage, rather than inside the residence.

Officials said they found extensive lighting and heating systems, fertilizers and other equipment used to cultivate cannabis at the site.

“These investigations are complicated, and they have been months in development,” Lancaster said. “There appears to be a pattern of operations at each one of these locations.”

Dongming Liao, 41, was arrested at the scene and charged with illegal cultivation of marijuana. Lancaster said it was unclear if Liao is a legal resident of the United States.

Officials said they also confiscated a 2017 Ford Transit van, $1,882 in suspected drug proceeds and “illegal drug-related documentation” at the residence.

Lancaster declined to say if the operation was directly connected to others that have been raided in recent months, instead saying it was part of a larger effort to stamp out the cultivation sites.

More than two dozen similar sites have been uncovered in Somerset and Kennebec counties since the first bust in January, with officials suspecting there could be as many as 400 more across Maine.

Lancaster said officials had been monitoring activity for months at the residence in Harmony as part of a broader investigation into dozens of suspected illegal marijuana growing operations in rural areas of central Maine.

The search warrant was conducted by a team that included Somerset County Sheriff’s Office detectives and deputies, the Waterville Police Department, the federal Drug Enforcement Administration, the U.S. Department of Homeland Security, U.S. Customs and Border Protection and investigators from the Maine Office of Cannabis Policy.

Liao is being held at the Somerset County Jail in Madison. His bail has been set at $5,000 cash.

His initial court appearance is scheduled for July 3.