The militiamen occupying a federal building in Oregon over a grazing rights dispute have refused to leave until land is handed over to ranchers.

The Bundy family, which is leading the occupation, said they were willing to stay inside the headquarters of a national wildlife refuge until the authorities 'restore the rights to people so they can use the land and resources'.

Ryan Bundy said the federal government has been 'tromping on people's rights and privileges and properties and livelihoods', and called for the 187,000-acre refuge to be shut down and returned to the hands of ranchers.

They were originally demonstrating in support of ranchers Dwight Hammond Jr, 73, and his 46-year-old son Steven Hammond - who are bound for jail on Monday morning for burning federal land to stop invasive plants from growing in 2001 and 2006.

However the Hammonds - who said they would report to prison peacefully - have distanced themselves from the armed protesters and said they are nothing to do with them.

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Protesters march on Court Avenue in support of an Oregon ranching family facing jail time for arson in Burns, Oregon, on Saturday. Soon after, they occupied Malheur National Wildlife refuge building in Princeton, Oregon

Arizona cattle rancher LaVoy Finicum leads a tour through the Malheur National Wildlife Refuge near Burns

The Bundy family (Ammon Bundy pictured) said they were willing to stay inside the headquarters of a national wildlife refuge until the authorities 'restore the rights to people so they can use the land and resources'

Father and son Dwight (left) and Stephen Hammond (right) say they plan to comply with law enforcement - and insist the armed demonstrators are nothing to do with them

The Hammonds served jail time for arson three years ago but a judge has ruled their initial sentences were insufficient.

Their attorney said told CBS the demonstrators do not speak for them, with the father and son expected to report to jail on Monday morning.

But Ryan Bundy, speaking at he Malheur National Wildlife Refuge south of Burns, Oregon, said he and his group of protesters had no intention of leaving, vowing to stay there 'for years' if needed.

He the Oregonian that they're 'willing to kill and be killed' if necessary, adding that the federal officials' actions have been 'in violation of the constitution'.

BUNDY FAMILY LINKED TO RON AND RAND PAUL CAMPAIGNS Cliven and Ryan Bundy met privately with Republican presidential candidate Rand Paul at an event in Kentucky last year, Politico reported. Cliven Bundy said he spoke with Paul for around 45 minutes in a back room at a casino, which the senator's campaign denied. The Bundy family previously donated to Rand's father Ron Paul during his presidential campaigns in 2008 and 2012. BuzzFeed reported that Ryan Bundy donated a total of $613 to Ron Paul in 2007 and 2008. Meanwhile Ammon Bundy gave $1,000 to Ron Paul's campaign in 2008 and $500 in 2012. Advertisement

'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,' Ryan Bundy said.

He added: '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.'

Much of the 187,000-acre refuge was once in the hand of ranchers but was moved into federal possession in the early 1900s.

The protesters claimed to have as many as 150 supporters with them inside the federal property, which is managed by the US Fish and Wildlife Service and was closed for the holiday weekend.

The stand-off has led Harney County School District 3 to cancel all classes for the entire of this week to ensure 'staff and student safety', KTVZ reported.

They later said they would not disclose how many people demonstrating because of 'operational security', and reporters at the scene could only see a dozen or so cars outside the building.

'We're planning on staying here for years, absolutely,' Ammon Bundy, one of the occupiers, told the Oregonian via telephone. ‘This is not a decision we've made at the last minute,' he added.

Ammon Bundy and his brother Ryan, who is another occupier, are the sons of of Nevada rancher Clive Bundy, who was involved in a 2014 standoff with the government over grazing rights.

The occupation came shortly after 300 marchers paraded through Burns, Oregon, about 50 miles away, to protest at the prosecution of father and son Harney County ranchers Dwight Hammond Jr and Steven Hammond, who were ordered returned to prison by a federal court which ruled their original sentences were insufficient.

The group was demanding that the Hammonds be released and that the federal government give up control of the Malheur National Forest.

Dwight Hammond, 73, and Steven Hammond, 46, said they lit the fires in 2001 and 2006 to reduce the growth of invasive plants and protect their property from wildfires.

The two were convicted of the arsons three years ago and served time - the father three months, the son one year.

But a judge ruled their terms were too short under federal law and ordered them back to prison for about four years each.

Ammon Bundy said that while the occupiers were not looking to hurt anyone, they would not rule out violence if police tried to remove them.

The brothers said their real goal is to simply start a movement. It is unknown what types of weapons are now at the refuge building, but there are no hostages in the area.

'The facility has been the tool to do all the tyranny that has been placed upon the Hammonds,' they told the Oregonian.

Ammon Bundy posted a video on his Facebook page asking for people to come help him. Below the video is this statement: 'ALL PATRIOTS ITS TIME TO STAND UP NOT STAND DOWN!!! WE NEED YOUR HELP!!! COME PREPARED.'

Ammon Bundy said the group planned to stay at the refuge indefinitely.

'The facility has been the tool to do all the tyranny that has been placed upon the Hammonds,' the Oregonian quoted Ammon Bundy as saying.

A watch tower is manned at the Malheur National Wildlife Refuge near Burns. Self-styled militiamen are occupying the headquarters of the U.S. wildlife refuge in eastern Oregon

Ryan Payne, an Army veteran from Montana, participates in a community meeting in Burns, Oregon. He is among key militiamen who seized control of the refuge on Saturday

'This is not a decision we've made at the last minute,' he added, calling on other militiamen to join them.

The Bundys are the sons of Nevada rancher Cliven Bundy. The Bundy family ranch in Bunkerville, Nevada, some 80 miles northeast of Las Vegas, was the site of an armed protest against the US Bureau of Land Management in April 2014.

MILITIAMEN'S CALLS TO ARMS In a video posted to Facebook by Sarah Dee Spurlock, two men - one donning camouflage gear - explain why they are taking the measures they are. FIRST MILITIAMAN: 'This will become a base place for patriots from all over the country to come to be housed and live here. 'We're planning on staying here for several years.And While we're here, what we're going to be doing is we're going to be freeing these lands up, getting the ranchers back to ranching, getting the miners back to mining, getting the loggers back to logging, where they can do it under the protection of the people. 'And not be afraid of this tyranny that's upon them. And what'll happen is Harney County will begin to thrive again. 'One time they were the wealthiest county, now they're the poorest, and we will reverse that in just a few years by freeing up their land and resources. 'And we're doing this for the people. We're doing this so the people can have their land and their resources back where they belong. 'We're calling people out here to come and stand. We need you to bring your arms and we need you to come to the Malheur National Wildlife refuge.' SECOND MILITIAMAN: 'Until that line is drawn to say "We've had enough of this tyranny, you are going to leave us alone, it will not change". 'This is the power of America right here. People got together for this and it doesn't have to stop here. 'This could be a hope that spreads through the whole country. Everybody's looking for this hope because the government has beat us, oppressed us and took everything from us. They will not stop until we tell them no.' Advertisement

The stand-off gained nationwide attention as the agency sought to seize cattle because the elder Bundy refused to pay grazing fees.

The federal agents ultimately backed down, citing safety concerns, and gave back hundreds of Bundy cattle which they had rounded up.

In a video posted to Facebook by Sarah Dee Spurlock, two men - one donning camouflage gear - explain why they are taking the measures they are.

'This will become a base place for patriots from all over the country to come to be housed and live here. We're planning on staying here for several years, the first man said.

He added: 'One time [Harney County] were the wealthiest county, now they're the poorest, and we will reverse that in just a few years by freeing up their land and resources.

'And we're doing this for the people. We're doing this so the people can have their land and their resources back where they belong.'

He appealed to the public for people to join the group in Oregon.

'We're calling people out here to come and stand. We need you to bring your arms and we need you to come to the Malheur National Wildlife refuge,' he said.

The second man, dressed in camouflage gear, said the group is challenging the government.

'Until that line is drawn to say "We've had enough of this tyranny, you are going to leave us alone", it will not change,' he said. 'This is the power of America right here.

'People got together for this and it doesn't have to stop here. This could be a hope that spreads through the whole country.

'Everybody's looking for this hope because the government has beat us, oppressed us and took everything from us. They will not stop until we tell them no.'

In another video, Jon Ritzheimer, a Phoenix-based anti-Islam activist and militiaman, says goodbye to his family, suggesting he plans to occupy the federal lands as well.

'The oppression and the tyranny that's taken place in Oregon - we know it's taken place all across the US - the Bundy Ranch was prime example. And we the people need to take a stand,' he said in the 13-minute video.

He goes on a lengthy rant about the legal system and how it treated the Hammond family.

A sign tacked outside a Burns. Oregon, home reflects growing community sentiment that outsider militia aren't welcome, in mid-December 2015. The prosecution of Dwight and Steven Hammond for burning public lands has brought fresh focus to the debate over how federal land is managed

Militia members claimed on Saturday to have as many as 150 supporters, like the one pictured above, at the national wildlife refuge in Oregon

A private sign welcomes visitors to the Diamond Valley, part of the Harney Basin in southeast Oregon, in mid-December 2015. The valley is home to large cattle ranches that rely on both private and public land for grazing.

'They are not terrorists....This oppressive, tyrannical government who really has no jurisdiction here - this is Hardy County's land,' he said.

He added: 'The Hammonds were not tried by a jury of their peers. There's an indictment with no signatures on it.

'This is a cruel and unusual punishment. But this federal government comes in here and says no, that's not enough, they need to do a minimum of five years.'

Ritzenheimer then makes a call to arms.

He said: 'It's real simple, Dwight. Do you want to die in prison labeled a terrorist by these oppressors or do you want to die out here with us as a free man? I want to die a free man.'

'If you do not spearhead this and take a stand, it's going to set a new precedent across the US.

'They get stronger and think they can continue to go around and bully we, the people. But when we unite and you take that stand there's no stopping us.'

Beth Anne Steele, an FBI spokeswoman in Portland, told The Associated Press that the agency was aware of Saturday’s situation at the national wildlife refuge. She made no further comment.

Harney County Sheriff Dave Ward released a statement late on Saturday night.

Ward said: '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.

In one YouTube video, Jon Ritzheimer, a Phoenix-based anti-Islam activist and militiaman, suggests he is going to join the occupied federal lands and says goodbye to his family

Ritzheimer wipes tears from his eyes he speaks about his wife before going on a lengthy rant about the legal system

'More information will be provided as it becomes available. Please maintain a peaceful and united front and allow us to work through this situation.'

Some local residents feared the Saturday rally would involve more than speeches, flags and marching. But the only real additions to that list seemed to be songs, flowers and pennies.

As marchers reached the courthouse, they tossed hundreds of pennies at the locked door. Their message: civilians were buying back their government. After the march passed, two girls swooped in to scavenge the pennies.

A few blocks away, Hammond and his wife Susan greeted marchers, who planted flower bouquets in the snow. They sang some songs, Hammond said a few words, and the protesters marched back to their cars.

Dwight Hammond has said he and his son plan to peacefully report to prison January 4 as ordered by the judge.

The decision to extend the Hammonds’ prison terms has generated controversy in a remote part of the state.

In particular, the Hammonds' new sentences touched a nerve with far right groups who repudiate federal authority.

Ammon Bundy and a handful of militiamen from other states arrived last month in Burns, some 60 miles from the Hammond ranch.

In an email to supporters, Ammon Bundy criticized the US government for a failed legal process.

Two of the main occupiers, Ammon and Ryan Bundy are the sons of Rancher Cliven Bundy (pictured here in 2014), who was locked in a decades-long dispute with the Bureau of Land Management over grazing rights

Protesters gather at the Bureau of Land Management's base camp, where cattle that were seized from rancher Cliven Bundy are being held, near Bunkerville, Nevada, in 2012