Kerry: Samples Test Positive for Sarin

Secretary of State John Kerry says that samples taken from Syria have tested positive for Sarin, adding to a mountain of evidence that proves Assad is culpable for a recent chemical weapon attack that killed hundreds in Syria. "In the last 24 hours, we have learned through samples that were provided to the United States that have now been tested from first responders in east Damascus and hair samples and blood samples have tested positive for signatures of Sarin," Kerry said on NBC's Meet The Press. Sarin is an odorless, colorless nerve agent that the CDC says is one of the most toxic and volatile chemical weapons in existence.