Marissa Shephard pleads not guilty in death of Baylee Wylie

Jury selection is underway at the trial of a woman accused in the brutal killing of a young man from Moncton, New Brunswick.

Marissa Shephard pleaded not guilty in court Monday morning to first-degree murder and arson in the death of 18-year-old Baylee Wylie -- who was severely beaten while tied to a chair and stabbed up to 200 times in a burned apartment in December 2015.

Shephard was arrested on a Canada-wide warrant two years ago and waived her right to a preliminary hearing.

She is the third person to stand trial in Wylie's death -- 19-year-old Devin Morningstar was convicted of first-degree murder and arson while 19-year-old Tyler Noel pleaded guilty to second-degree murder and arson.