BURNS —

The FBI and Oregon State Police on Tuesday arrested the leaders of an armed group that has occupied the Malheur National Wildlife Refuge for the past three weeks, conducting a traffic stop that prompted gunfire — and one death — along a highway through the frozen high country.

Militant leader Ammon Bundy and his followers were reportedly heading to a community meeting at the senior center in John Day to address local residents to discuss their views on federal management of public lands.

The Oregonian newspaper reported several hundred people had gathered at the John Day Senior Center on Tuesday evening and were told the “guest speakers” would not be appearing.

The dead man was identified by his daughter as Robert “LaVoy” Finicum, 55, of Cane Beds, Arizona. Finicum was a frequent and public presence at the refuge, often speaking for the group at news conferences.

Arianna Finicum Brown confirmed her father’s death to The Oregonian, saying “he would never ever want to hurt somebody, but he does believe in defending freedom and he knew the risks involved.”

In a statement, the FBI and OSP said agents had made eight arrests, including Bundy.

Each will face a federal felony charge of conspiracy to impede officers of the United States from discharging their official duties through the use of force, intimidation or threats, authorities said. No indictments or federal charging documents had been made public.

OSP confirmed its troopers were involved in the traffic-stop shooting, though neither agency released details about what started it. One of those arrested, described only as a man, suffered nonlife-threatening wounds and was treated at a hospital, the agencies said. No law enforcement personnel were injured.

The Deschutes County Major Incident Team will be assisting OSP and the Harney County District Attorney’s Office with the investigation into the shooting.

An AirLink helicopter from St. Charles Bend was sent Tuesday night to Harney County, but hospital spokeswoman Lisa Goodman confirmed just after 8 p.m. St. Charles would not receive patients from Harney County. Several Bend Police cars were parked outside the hospital’s emergency care department amid a lockdown at the medical center, which would stay in place overnight, the hospital said. Hospital security questioned people before letting them enter the emergency department doors, explaining the facility was in lockdown.

Ammon Bundy’s group, which has included people from as far away as Arizona and Michigan, seized the headquarters of the Malheur National Wildlife Refuge on Jan. 2 as part of a long-running dispute over public lands in the West. Law enforcement officers converged on the wildlife refuge after the arrests and were expected to remain at the site throughout the night; it was unclear how many people, if any, remained in the buildings.

The confrontation came amid increasing calls for law enforcement to take action against Bundy for the illegal occupation of the wildlife refuge. Authorities previously had taken a hands-off approach, reflecting lessons learned during bloody standoffs at Waco, Texas, and Ruby Ridge, Idaho, during the 1990s.

Many residents of Harney County, where the refuge is located, have been among those demanding that Bundy leave. Many sympathize with his criticism of federal land management policies of public lands but opposed the refuge takeover. They feared violence could erupt.

Bundy recently had begun traveling into Grant County to try to drum up more sympathy for his cause.

“I am pleased that the FBI has listened to the concerns of the local community and responded to the illegal activity occurring in Harney County by outside extremists,” U.S. Sen. Jeff Merkley, D-Ore., said in a written statement. “The leaders of this group are now in custody and I hope that the remaining individuals occupying the Malheur National Wildlife Refuge will peacefully surrender so this community can begin to heal the deep wounds that this illegal activity has created over the last month.”

Gov. Kate Brown, who in recent days had called strongly for a resolution, said in a statement late Tuesday, “The situation in Harney County continues to be the subject of a federal investigation that is in progress. My highest priority is the safety of all Oregonians and their communities. I ask for patience as officials continue pursuit of a swift and peaceful resolution.”

The Bundys are the sons of Nevada rancher Cliven Bundy, who was involved in a high-profile 2014 standoff with the government over grazing rights.

The militants, calling themselves Citizens for Constitutional Freedom, came to Eastern Oregon to decry what they call onerous federal land restrictions and to object to the prison sentences of two local ranchers convicted of setting fires.

Specifically, the group wanted federal lands turned over to local authorities. The U.S. government controls about half of all land in the West.