WALKER, Minn. (AP) — A Cass County grand jury has upgraded the charges against a Cass Lake man accused in the killing of his ex-girlfriend to first-degree premeditated murder

County prosecutors announced the new charges Friday against 27-year-old Ross Z. Littlewolf.

He had previously been charged with second-degree murder, but because a conviction for first-degree premeditated murder carries a mandatory life sentence without parole, it can only be charged by a grand jury.

Prosecutors allege Littlewolf fired a shotgun blast through a sliding glass door to enter the Cass Lake home of 22-year-old Kandace Blaine Dunn and then shot her in the head June 26.

Dunn was sharing a room with her two young children — one of whom is also Littlewolf’s child.

Leech Lake tribal police arrested Littlewolf a short time later.

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