"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, an Idaho militia leader, said that while the occupiers were not looking to hurt anyone, they would not rule out violence if police tried to remove them, the Oregonian reported.
Bundy's brother Ryan Bundy, who is also an occupier, told 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'.
'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 told the Oregonian.
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.'
The brothers said, however, that 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,' 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: "(asterisk)(asterisk)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."
The jury convicted both of the Hammonds of using fire to destroy federal property for a 2001 arson known as the Hardie-Hammond Fire, located in the Steens Mountain Cooperative Management and Protection Area. Witnesses at trial, including a relative of the Hammonds, testified the arson occurred shortly after Steven Hammond and his hunting party illegally slaughtered several deer on BLM property. Jurors were told that Steven Hammond handed out “Strike Anywhere†matches with instructions that they be lit and dropped on the ground because they were going to “light up the whole country on fire.†One witness testified that he barely escaped the eight to ten foot high flames caused by the arson. The fire consumed 139 acres of public land and destroyed all evidence of the game violations. After committing the arson, Steven Hammond called the BLM office in Burns, Oregon and claimed the fire was started on Hammond property to burn off invasive species and had inadvertently burned onto public lands. Dwight and Steven Hammond told one of their relatives to keep his mouth shut and that nobody needed to know about the fire.