Six deer hunters have been shot dead and two injured in the US state of Wisconsin in an argument over a tree stand, the local sheriff's office said.
Wisconsin issued nearly 640,000 deer hunting licences this year
Tree stands are aerial platforms used by hunters to get a shot at passing deer from above.
A man has been arrested over the shootings, which happened on Sunday, the second day of Wisconsin's popular nine-day annual deer-hunting season.
Chai Vang, 36, was arrested carrying an assault rifle, local police said.
Wisconsin's hardwood forests make it prime deer-hunting territory and the sport is a popular family pastime there.
Nearly 640,000 deer licences were distributed for this year's hunting season, the Minneapolis and St Paul Pioneer Press in neighbouring Minnesota reported on its website.
The shootings happened when a party of hunters returning to their hunting shack near the small town of Birchwood spotted a man in one of their tree stands, said Sawyer County deputy sheriff Tim Zeigle.
The exact course of events was not immediately clear but, according to the Associated Press, when the group challenged him he came down from the stand and opened fire.
Five people including a teenage boy and a woman were killed immediately while a sixth man died of his injuries on Monday. Both of the injured people remain in hospital.
The arrested man was wearing a numbered orange licence vest - obligatory for hunters - and carrying a high powered assault rifle, the deputy sheriff said.
According to AP, no charges have yet been filed against Mr Vang.
Wisconsin is among the top US states for deer-hunting. The animals are so widespread that last year 530 were killed in the streets of Superior, a small city in north-west Wisconsin, one fifth of them in traffic accidents and the rest by licensed archers.
The Wisconsin Department of Natural Resources runs a scheme under which hunters can donate their dead deer to feed the state's needy.