(REUTERS) -- Federal agents on Wednesday closed in on the last four anti-government militants still holed up at a national wildlife refuge in Oregon after a 40-day armed occupation protesting federal land control in the West.
The Federal Bureau of Investigation said that no shots had been fired and that negotiations were continuing to end the standoff at the Malheur National Wildlife Refuge in remote eastern Oregon without violence.
The FBI said the latest confrontation began after one of the protesters was seen riding an all-terrain vehicle outside the encampment.
A number of the occupiers were relating their account of events as they unfolded via an independent Internet broadcast, "Revolution Radio," that is known to be sympathetic to the occupation.
The militants said FBI agents had moved to within 50 yards (45 meters) of the occupiers' position in the compound, and one reported seeing FBI snipers on a nearby hillside with high-beam vehicle lights trained on the compound.
"If they tear gas us, it's the same as firing on us," said one of the occupiers, who identified herself as Sandy Anderson. "Don't come in. Don't do it."
She later reported that federal agents were trying to coax the protesters out of hiding, but added, "We're not leaving without our weapons."
Nevada state Assembly member Michele Fiore, a Republican supportive of the protesters, identified herself over the broadcast as she talked with the occupiers via telephone. She said she was in Portland waiting for an FBI escort to Malheur, roughly 300 miles (480 km) to the southeast, in order to help broker a peaceful resolution to the standoff.
Images from the standoff:
The broadcast was frequently interrupted by the sounds of the protesters shouting and law enforcement officers calling out to them by bullhorn. Fiore repeatedly tried to calm the occupiers by leading them in prayers over the phone.
FOUR HOLDOUTS STILL FACE CHARGES
The four remaining protesters were indicted last week along with 12 others previously arrested on charges of conspiring to impede federal officers during the occupation.
The takeover at Malheur, which began on Jan. 2, was sparked by the return to prison of two Oregon ranchers convicted of setting fires that spread to federal property in the vicinity of the refuge.
The occupation, led by Idaho rancher Ammon Bundy, also was directed as a protest against federal control over millions of acres public land in the West.
Cliven Bundy, his father, was arrested on Wednesday when he arrived at Portland International Airport on his way to the wildlife refuge to support the militants, according to the Oregonian newspaper.
Cliven, 74, faces conspiracy and weapons charges, the paper reported. He lead a 2014 standoff with the government over Nevada grazing rights that ended with federal agents backing down in the face of about 1,000 armed militiamen.
Ammon Bundy and 10 others were arrested in January in Oregon, most of them during a confrontation with the FBI and state police on a snow-covered roadside where a spokesman for the group, Robert "LaVoy" Finicum, was shot dead. A 12th member of the group turned himself in to police in Arizona.
The FBI said its agents moved to contain the remaining four holdouts Wednesday evening after one of the occupiers drove an all-terrain vehicle outside the barricades previously set up by the self-styled militia members at the refuge.
FBI agents attempted to approach the driver, and he sped away back to the compound, after which federal agents "moved to contain the remaining occupiers by placing agents at barricades both immediately ahead of and behind" their encampment, the FBI said.
Until Wednesday, FBI and police had largely kept their distance from the buildings occupied by the militants, sealing off access to the refuge headquarters with roadblocks.
"However, we reached a point where it became necessary to take action" to ensure everyone's safety, Greg Bretzing, special agent in charge of the FBI in Oregon, said in a statement.
The fate of Bundy and other members of the group who remain in custody has been clouded by the four holdouts, who joined the protest after it started but have so far refused to leave. A judge has cited the continuing standoff as a major obstacle to the release of at least some of those who remain jailed on federal charges.
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