Bundy, who led a 2014 stand-off over Nevada grazing rights, was arrested on Wednesday at Portland International Airport while on his way to the Oregon wildlife refuge to support the militants.
After a near-confrontation between one of the occupiers and the FBI Wednesday afternoon, the bureau stationed agents around the occupiers' encampment.
Two Indigenous people remember the Oka crisis, and have some experience going head-to-head with the Canadian government.
The standoff in Oregon and tentative support it has garnered from Republican leaders reveals the party's deeply held antagonism toward environmental protections.
'We Are Going to Light Up the Whole Country on Fire': The Arson That Led to the Oregon Militia Standoff
The ongoing occupation of a wildlife refuge by armed militiamen was sparked by the imprisonment of two ranchers for setting a blaze in 2001 that scorched 139 acres.