An occupy movement of ranchers and concerned citizens of an Oregon wildlife refuge may be coming to a close after a 40-day holdout.

On Wednesday evening, FBI agents moved armored vehicles within 50 feet of the building at Malheur National Wildlife Refuge where the remaining four weapon-wielding individuals have resided, according to a live audio stream between one of the occupiers and Nevada Assemblywoman Michele Fiore.

Despite mounting pressure from federal agents, the occupiers, David Fry of Ohio, Jeff Banta of Nevada, and Sean and Sandy Anderson of Idaho, have said they will not surrender unless all charges against them are dropped. On Wednesday, they doubled down on a previous request that evangelist Franklin Graham facilitate the negotiations Thursday.

The occupiers said in the live call that they would leave the facility alongside Fiore and Graham, who is currently on a national prayer tour, but the FBI said it will not allow anyone into the refuge. Fiore and Mike Arnold, the lawyer for Ammon Bundy, confirmed they had departed Portland International Airport Wednesday night for the Burns refuge.

On January 2, Bundy and others took over the wildlife headquarters. One of the occupiers, Robert "LaVoy" Finicum, a rancher from Arizona was fatally shot by law enforcement on January 26 during a traffic stop arrest. The other individuals in the car were arrested on federal charges of conspiracy and remain in jail.