LONGMONT, Colo. (AP) — A prosecutor in northern Colorado says a 15-year-old arrested in the stabbing death of a 19-year-old woman had a "death list" that included the victim's younger sister.

Boulder Country Deputy District Attorney Michael Foote told a judge that the teen stabbed Makayla Grote at an apartment complex Saturday night and then pursued the younger sister, who locked herself in a room.

The boy declined to appear at his first court hearing Monday after being arrested Sunday on suspicion of first-degree murder.

The Longmont Times-Call reports that prosecutors said police found the teen about a mile from the home of another person on the list.

Prosecutors also said the boy assaulted his grandfather and threatened his mother with a knife the day before Grote's killing.