At least six park rangers were shot and killed and several others wounded Sunday in Virunga National Park in the Democratic Republic of Congo. While no one has claimed responsibility for the attack, officials are blaming one of the many militia groups that vie for control of natural resources in the endangered gorillas' habitat. CBS News foreign correspondent Debora Patta joins Anne-Marie Green on CBSN AM to talk about how the great apes and their protectors get caught in the crossfire in the unstable border area.