The Preparation for the Mass Shooting

Jill Biden laid flowers at a memorial outside the school where three kids and three adults were killed in Monday's mass shooting. CBS News has learned the Covenant school shooter, seen here walking the hallways within a salt style firearm, had weapons training before the attack. Investigators say the shooter, 28-year-old Audrey Hale, purchased seven firearms legally and had been hiding them at home. The two semi-automatic weapons Hale was armed with are designed to do damage.