At last, the eyewitness testimony U.N. investigators have been waiting for.<br/> <br />Amateur video appears to show a victim of last week's apparent poison gas attack outside Damascus speaking with the U.N. chemical weapons team that's come to investigate.<br/> <br />SOUNDBITE (Arabic) UNIDENTIFIED MALE VICTIM, SAYING<br/> <br />"There are chemicals, and then we went outside to bring ambulances, (translator asks, what did you feel?) I started to get dizzy, and I couldn't see anymore, and I wanted to throw up. I didn't see in front of me and then I fell down. The situation is very bad.''<br/> <br />The U.N. convoy came under sniper fire earlier in the day. It's unclear by which side in Syria's protracted civil war.<br/> <br />U.S. Secretary of State John Kerry said evidence of the massive chemical attack was "undeniable" -- signaling the U.S. was edging closer to a possible military response.<br/> <br />(SOUNDBITE) U.S. SECRETARY OF STATE JOHN KERRY<br/> <br />"Make no mistake. President Obama believes there must be acc
