BURNS, Ore. -- One person was killed and another wounded as federal and state authorities arrested the leader of an armed group that has occupied a national wildlife refuge in Oregon for more than three weeks and five of his followers, the FBI said late Tuesday.

The FBI said authorities arrested Ammon Bundy, 40, his brother Ryan Bundy, 43, Brian Cavalier, 44, Shawna Cox, 59, and Ryan Payne, 32, during a traffic stop Tuesday afternoon on U.S. Highway 395.

Authorities said another person, Joseph Donald O'Shaughnessy, 45, was arrested by Oregon State Police in Burns. Later Tuesday evening, the FBI arrested Peter Santilli, 50, in Burns.

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In addition, the FBI says Jon Ritzheimer, 32, was arrested in Arizona on a federal charge related to the wildlife refuge takeover in Oregon. The agency said Ritzheimer turned himself in to police in Peoria, Arizona and was arrested without incident

Shots were fired during the arrest and one person was killed. The person's identity was not released, pending notification of his next of kin. The FBI said he was the "subject of a federal probable cause arrest."

Another person suffered non-life threatening injuries and was transported to a local hospital for treatment, the FBI said. He was arrested and is currently in custody.

Each person arrested faces a federal felony charge of conspiracy to impede U.S. officers from discharging their official duties through the use of force, intimidation, or threats, the FBI said.

Oregon Gov. Kate Brown issued a statement late Tuesday saying in part, "The situation in Harney County continues to be the subject of a federal investigation that is in progress. ... I ask for patience as officials continue pursuit of a swift and peaceful resolution."

The group began occupying the Malheur National Wildlife Refuge in eastern Oregon on Jan. 2 to protest federal land use policies. Bundy is the son of Nevada rancher Cliven Bundy, who was involved in an armed standoff with the government over grazing rights in 2014.

Highway 395 at the intersection of U.S. 20 north of Burns -- not far from the wildlife refuge -- was closed in both directions Tuesday night, CBS affiliate KOIN reported.

Bundy and his followers were reportedly heading to a community meeting at the senior center in John Day, a Grant County town about 70 miles north of Burns, to address local residents to discuss their views on federal management of public lands.

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.

"We continue to work with Harney County Sheriff Dave Ward and his deputies; Oregon State Police; and the United States Attorney's Office to address any further outstanding issues," the FBI said.

Last week, Bundy began speaking with federal authorities. On Thursday, he went to the airport in Burns, close to where federal officials had set up a staging area.

With reporters watching, Bundy spoke on the phone, apparently with an FBI negotiator. The conversation was streamed online by another member of his group.

At the time, Bundy said his group was "not going to escalate" the situation, and he agreed to speak with authorities again.

KOIN reported Bundy was seen after the meeting leading a group of trucks out of the FBI headquarters and into town, and it did not appear the group was heading back toward the refuge.

Militiamen from around the country have gone to Burns to join the group's cause, KOIN said.

Bundy reportedly met with his top-ranking counterparts for several hours on last Wednesday, but kept a tight lip about what was actually discussed.

The heavily armed group said they believe their cause was not only just, but an act of divine intervention.

"God wants us here, there's a sense that's beckoning and it comes from heaven," militiaman Kelly Gneiting told KOIN. "We're doing what's right, we're doing what the founding fathers would do because we're inspired by God, also."

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

In recent days, Gov. Brown stepped up her public comments urging an end to the standoff. In a one-on-one interview with KOIN on Monday, Brown said it was "intolerable" for the militia to be allowed to remain.

"It is absolutely unacceptable for this to continue," Brown said. "The very fabric of the Burns community is being ripped apart by this occupation."

The Burns Paiute Tribe also asked the U.S. Department of Justice to prevent the armed group from moving freely on and off the national wildlife refuge.