"We can't have an American people that violate the law and then just walk away from it," the Nevada Democrat told Reno, Nev., TV station KRNV TV on Monday. "So it's not over."
The Bureau of Land Management says cattle rancher Cliven Bundy has illegally trespassed on federal lands since the 1990s and owes more than $1 million in back grazing fees.
The bureau on Saturday released about 400 head of cattle it seized from Bundy after angry protesters — some armed with firearms — gathered at his ranch in his support.
Bundy says he doesn't recognize federal authority of the land and insists it belongs to Nevada.
Many of the protesters supporting Bundy left the ranch after the cattle was returned. But some remain, saying they suspect federal agents will return this week.
"I feel sorry for any federal agents that want to come in here and try to push us around," Bundy supporter Jarad Miller told KRNV. "I really don't want violence toward them, but if they're gonna come bring violence to us — well, if that's the language they want to speak, we'll learn it."
Bureau of Land Management spokesman Craig Leff said "the door isn’t closed" to resolving the matter "administratively and judicially."