The parents of a 15-year-old boy who shot dead four students at his Michigan high school are being held on 1.4 million dollars bail

James and Jennifer Crumbley were arrested in Detroit, after failing to show up for a court appearance.

They have pleaded not guilty to involuntary manslaughter -- after it was found they bought the gun for the teen and apparently ignored his threats of violence.

Their son Ethan is in the same jail as they are.