News Wrap: 9 Americans killed in brutal Mexican ambush

In our news wrap Tuesday, nine Americans, including six children, were brutally killed in an ambush in northern Mexico, about 75 miles south of the U.S. border. Mexican officials are investigating whether the attack was a case of mistaken identity. Also, Iran has announced it will start injecting uranium gas into centrifuges at its Fordo nuclear facility — turning it into an active atomic site.