Ricin confirmed in letter to Obama

The FBI has confirmed at least two letters – one intended for the president, another for a U.S. senator – and a mail screening facility have all tested positive for ricin.

The Bureau says it has questioned an individual in Mississippi who investigators believe is responsible for both letters. Security has been ramped up in Washington. Experts say ricin is very toxic. Brittany Gogo spoke to some today to see why this substance is so deadly.