twitching uncontrollably. >> others show the desperate attempts to resuscitate the lifeless bodies of young children. i know this is so hard to watch. on thursday, senators were told there were multiple reasons that the clips are authentic, that they were shot from multiple angles. the outdoor footage, apparently, matched overhead imagery, and they were corroborated by survivors. >> cnn's barbara starr is at the pentagon. barbara, the video may be strong evidence of a sarin gas attack. that's what the u.s. government is saying. is it still or has it yet proven that the syrian regime carried out this attack? >> reporter: well, good morning, victor and christi. i think the administration feels very strongly that the syrian regime is responsible, even if they do not yet have that final piece of intelligence that bashar al assad himself ordered it. they're going to look for that, we understand.