Teen pleads guilty in Michigan school shooting that left four students dead

A teenager pleaded guilty Monday to terrorism and first-degree murder in a Michigan school shooting that killed four students and put an extraordinary focus on the boy's home life and the alleged role of his parents in the tragedy.

Ethan Crumbley pleaded guilty to all 24 charges, nearly a year after the attack at Oxford High School in southeastern Michigan. In the gallery, some relatives of the victims were weeping as assistant prosecutor Marc Keast described the crimes.

"Yes," he replied, when asked if he "knowingly, willfully and deliberately" chose to shoot other students.