Nineteen-year-old Brok Junkermeier was charged with intentional second-degree murder Friday in Kandiyohi County. Two others, ages 16 and 17, also face charges.
Police found 79-year-old Lila Warwick Monday night after authorities went there to check on her welfare.
Prosecutors say Junkermeier said one of the teens thought Warwick had $40,000 in a safe, so they plotted to steal it.
Police say Junkermeier broke into Warwick’s Willmar home, cut her with a sword-like knife and forced her to write out a $1,500 check. Police say he then strangled her, repeatedly stabbed her, then threw her downstairs.
It was not immediately clear if Junkermeier had an attorney.