South Dakota investigators says that Attorney General Jason Ravnsborg reported hitting a deer with his car on Saturday night but actually killed a pedestrian whose body was not found until the next day.
Up to 250,000 are expected to attend the rally, which stretches on for nearly another week.
The scene Saturday at the 80th Sturgis Motorcycle Rally was familiar to veterans of the event, with throngs of maskless bikers packing the streets.
The annual gathering is a concern as the pandemic continues on
Hours before the event, protesters blocked a road leading to the monument. Authorities worked to move the demonstrators, mostly Native Americans protesting that South Dakota's Black Hills were taken from the Lakota people against treaty agreements.
Authorities say nine people have been killed after a plane crashed in South Dakota.