RCMP responded to a report of a shooting on the Lac La Ronge reserve Wednesday morning and found a man dead from a gunshot wound.
Police believe Natomagan, a member of the Lac La Ronge Indian Band, was abducted by Jonas Budd, who is her stepfather.
He's believed to be carrying a rifle and is considered dangerous, police said.
Police said they don't know where Budd might be headed, but he has connections in a number of Saskatchewan communities, including Cumberland House, Pinehouse, Sturgeon Landing and Prince Albert. He also has connections in Thompson, Man.
Natomagan was last seen just after 3 a.m. CST Wednesday at her residence.
Budd may be driving a grey, 2001 GMC Sierra 1500, extended cab, two-wheel drive with Saskatchewan plate 043 JEZ, police said.
Police are asking anyone with information to call 911 or the Amber Alert phone line at 1-877-762-6237.
Budd is not to be approached, police said.