More than 2,800 marijuana plants worth at least $750,000 have been found and destroyed at a sophisticated growing operation in the Boisfort...

BOISTFORT, Lewis County — More than 2,800 marijuana plants worth at least $750,000 have been found and destroyed at a sophisticated growing operation in the Boisfort Valley, authorities said.

Several individuals were under investigation following the discovery Sept. 21 on property owned by the Weyerhaeuser Co., Sheriff Steve Mansfield said in a news release issued late last week.

A loaded .22-caliber pistol and a rifle case were found at one of the campsites believed to be linked to the operation, and deputies also found tents, sleeping bags, food and gardening equipment, Mansfield added. Water had been piped from a river several hundred yards to holding ponds for irrigation.

“The growers were obviously armed and spending quite a bit of time tending and protecting their plants,” the sheriff wrote.

All the marijuana was destroyed, except for a few plants that were retained as evidence. Mansfield estimated the value of the pot found there and at two smaller growing operations nearby at $750,000 to $1 million.

Tips received during the summer led deputies to the site, which was in the same general area where 650 pot plants were seized a year ago, according to the news release.