Undersheriff: 3 students killed and 6 people injured in Michigan high school shooting; 15-year-old gunman arrested

Undersheriff: 3 students killed and 6 people injured in Michigan high school shooting; 15-year-old gunman arrested

OXFORD TOWNSHIP, Mich. -- Undersheriff: 3 students killed and 6 people injured in Michigan high school shooting; 15-year-old gunman arrested.