Suspect arrested for 'poison' letter to Obama

The FBI has identified the man suspected of an attempted biological attack on the U.S. President as Paul Kevin Curtis. He was arrested in the southern state of Mississippi, in the last few hours. Both Barack Obama and a U.S. Senator were sent envelopes - that preliminary tests show - were laced with ricin. That is a powerful poison that can cause death in as little as 36 hours. Al Jazeera's Patty Culhane reports from Washington.