A downstate man died in a snowmobile accident Saturday in Ogemaw county. The sheriff's department there says the accident happened shortly after noon in Rose Township. Deputies say 46 year old Stephen Cooper of Selby Township in Macomb County was riding with family and friends, when he lost control of his machine, striking a tree. He was transported to West Branch Regional Hospital where he later died. Deputies say he was a member of the Macomb County Sheriff's Mounted Posse. The accident remains under investigation.