The FBI on Tuesday arrested the leaders of an armed group that has occupied a national wildlife refuge in Oregon 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, a Grant  County town about 70 miles north of Burns, 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.

In a statement, the FBI and Oregon State Police said agents had made six arrests: Bundy, 40; his brother Ryan Bundy, 43; Brian Cavalier, 44; Shawna Cox, 59; and Ryan Payne, 32, during a traffic stop on U.S. Highway 395 Tuesday afternoon. Authorities said another person, Joseph Donald O’Shaughnessy, 45, was arrested in Burns.

One of those arrested suffered non-life-threatening wounds after shots were fired and was treated at a hospital, the agencies said. Another individual “who was a subject of a federal probable cause arrest is deceased,” they said.