Authorities Thursday identified three Laytonville residents and a fourth man as those arrested in connection with illegal marijuana gardens found on private land west of Laytonville.

Deputies made the arrests during the same Wednesday morning operation when an officer shot and killed a man suspected of guarding a pot crop, Mendocino County sheriff's officials said.

Gerald Stephenson, 52, Kelly Dutra, 41, and David Higgs, 50, all of Laytonville, were arrested along with 22-year-old Delfino Contreras, described as a transient, at a residence on the property where agents also uncovered marijuana plants, firearms and narcotic paraphernalia, Capt. Kurt Smallcomb said.

The suspects were discovered at about 6 a.m. as agents raided a residence off Branscomb Road on a 574-acre property called Mendocino Magic, a remote wooded property with rolling hills, a private campground and a reservoir known for its trout fishing.

Authorities Thursday were still investigating if those arrested were involved in two large marijuana gardens found nearby where violence erupted when deputies arrived, Smallcomb said.

Dutra apparently lived on the property. The other men's connection to the property was not known.

Brigid Holland, who also goes by Stacey, said her family has owned Mendocino Magic for many years. She said she suspected illegal growers had taken over remote parts of the land, which stretches over about a square mile, Holland said.

"There are certain areas I don't want to go," Holland said.

Renters are asked to sign a lease that specifically prohibits them from growing or using illegal substances on the property, she said. She doesn't travel to the property often from her San Francisco area residence and has had trouble monitoring activities, she said. She's asked law enforcement officials to help keep watch.

"I've said, &‘Please come every month and scour this property,'" Holland said.

Wednesday's operation involved a team of 60 officers from the sheriff's office, Mendocino's Major Crimes Task Force, Homeland Security and other federal and local agencies.

After the arrests at the house, two groups of officers split off and headed toward two areas where they believed large marijuana gardens had been planted, Smallcomb said.

At a site up a hill at about 7:45 a.m., five deputies encountered an armed man tending a patch of 426 marijuana plants.

A suspect brandished an assault weapon and was shot by three of the five deputies, according to Mendocino County Sheriff Tom Allman.

Authorities Thursday said they continue to seek the identity of the man shot and killed. Mendocino County officials have refused to release the names of the deputies involved.

Later, at a lower site on the property, deputies were fired on by four men. The deputies returned fire but the men fled into nearby woods, Smallcomb said.

Agents destroyed 1,980 marijuana plants at the scene.

Detectives investigated the gardens for a month before Wednesday's raids and believe they were connected to organize crime groups from Mexico, Sheriff Tom Allman said.

Stephenson was arrested on suspicion of possessing a firearm and ammunition as a felon, marijuana cultivation and sales, Smallcomb said.

Higgs was booked Thursday and was being held on $25,500 bail on suspicion of having a controlled substance and an assault rifle as well as tampering with a firearm's serial number, jail staff said.

Dutra was booked Thursday and was held on $15,000 bail on suspicion of marijuana cultivation and sales.