Update at 9:15 p.m.: Statement from Harney County Sheriff Dave Ward: "After the peaceful rally was completed today, a group of outside militants drove to the Malheur Wildlife Refuge, where they seized and occupied the refuge headquarters. A collective effort from multiple agencies is currently working on a solution. For the time being please stay away from that area. More information will be provided as it becomes available. Please maintain a peaceful and united front and allow us to work through this situation."

The Bundy family of Nevada joined with hard-core militiamen Saturday to take over the headquarters of the Malheur National Wildlife Refuge, vowing to occupy the remote federal outpost 30 miles southeast of Burns for years.

The occupation came shortly after an estimated 300 marchers -- militia and local citizens both -- paraded through Burns to protest the prosecution of two Harney County ranchers, Dwight Hammond Jr. and Steven Hammond, who are to report to prison on Monday.

Among the occupiers is Ammon Bundy, son of Nevada rancher Cliven Bundy, and two of his brothers. Militia members at the refuge claimed they had as many as 100 supporters with them. The refuge, federal property managed by the U.S. Fish and Wildlife Service, was closed and unoccupied for the holiday weekend.

In phone interviews from inside the occupied building Saturday night, Ammon Bundy and his brother, Ryan Bundy, said they are not looking to hurt anyone. But they would not rule out violence if police tried to remove them, they said.

"The facility has been the tool to do all the tyranny that has been placed upon the Hammonds," Ammon Bundy said.

"We're planning on staying here for years, absolutely," he added. "This is not a decision we've made at the last minute."

Neither man would say how many people are in the building or whether they are armed. Ryan Bundy said there were no hostages, but the group is demanding that the Hammonds be released and the federal government relinquish control of the Malheur National Forest.

He said many would be willing to fight -- and die, if necessary -- to defend what they see as constitutionally protected rights for states, counties and individuals to manage local lands.

"The best possible outcome is that the ranchers that have been kicked out of the area, then they will come back and reclaim their land, and the wildlife refuge will be shut down forever and the federal government will relinquish such control," he said. "What we're doing is not rebellious. What we're doing is in accordance with the Constitution, which is the supreme law of the land."

Government sources told The Oregonian/OregonLive that the militia also was planning to occupy a closed wildland fire station near the town of Frenchglen. The U.S. Bureau of Land Management posts crews there during the fire season.

Law enforcement officials so far have not commented on the situation. Oregon State Police, the Harney County Sheriff's Office and the FBI were involved.

Ammon Bundy posted a video on his Facebook page calling on patriots from across the country to report to the refuge - with their weapons.

"We went to the local communities and presented it many times and to many different people," he said. "They were not strong enough to make the stand. So many individuals across the United States and in Oregon are making this stand. We hope they will grab onto this and realize that it's been happening."

Among those joining Bundy in the occupation are Ryan Payne, U.S. Army veteran, and Blaine Cooper. Payne has claimed to have helped organize militia snipers to target federal agents in a standoff last year in Nevada. He told one news organization the federal agents would have been killed had they made the wrong move.

He has been a steady presence in Burns in recent weeks, questioning people who were critical of the militia's presence. He typically had a holstered sidearm as he moved around the community.

At a community meeting in Burns Friday, Payne disavowed any ill intent.

"The agenda is to uphold the Constitution. That's all," he said.

Cooper, another militia leader, said at that meeting he participated in the Bundy standoff in Nevada.

"I went there to defend Cliven with my life," Cooper said.

Ian K. Kullgren of The Oregonian/OregonLive contributed to this report.

-- Les Zaitz

503-221-8181; @leszaitz