Investigators with the San Luis Obispo County Sheriff’s Office completed a two-month investigation into a large marijuana cultivation operation, finding three growing sites located near Los Padres National Forest south of Santa Margarita Lake Road in the North County, authorities announced on Thursday.

Investigators said they confiscated 5,031 marijuana plants after detectives had to reach the site by helicopter, according to a Sheriff’s Office press release.

As a result of the investigation, on Tuesday a search warrant was served at a Bakersfield home. Evidence there led to the search of a second home.

Agents arrested a San Bernardino man and three Bakersfield men, and seized seven pounds of marijuana and six pounds of marijuana seeds.

All four suspects have immigration holds; the investigation is continuing and more arrests are expected.

The chopper was used to make 14 trips to remove trash from the area as well.