Pittsburgh synagogue attack, extremism in Brazil, Ai Weiwei in America

The man accused of carrying out the attack on Pittsburgh's Tree of Life Synagogue vented his anger at HIAS, a Jewish organization that helps refugees resettle in the US. We hear from the group's vice president. Also, the permafrost in the Arctic is no longer permanently frozen, and that's a problem for us all. Plus, a conversation with Chinese dissident artist Ai Weiwei.