Experts Say Cooperation, Engagement Can Reduce Mass Killings

Americans are trying to make sense of the mass shooting on Wednesday that claimed 17 lives at a Florida high school. Police say a 19-year-old former student, Nikolas Cruz, has admitted to the killings. As Mike O’Sullivan reports, school officials and experts who study violent crimes say more effort is needed to identify those at risk of committing violent acts, and limiting their access to lethal weapons