NEW: Arab League condemns attack, blames Syrian government
Kerry says blood and hair samples show "signatures of sarin"
The U.N. says its investigation will be "impartial and credible"
Syrian opposition: Obama has given false hope to those suffering
The Obama administration pushed forward Sunday on a new path toward military action in Syria, urging Congress to support the president’s call.
Tests found signatures of sarin gas in blood and hair samples collected from the Damascus site of an alleged chemical weapons attack, U.S. Secretary of State John Kerry said Sunday on CNN’s State of the Union.
The samples were collected separately from a United Nations investigation into the August 21 attack and provide further proof that the Syrian regime attacked its own people, Kerry said.