national mourning. it's national tragedy. many russians have lingering suspicions that maybe this plane was shot down. there is absolutely no evidence of that at the moment. none of the militant group or terrorist groups operating in egypt have the capability of shooting down a plane at 31,000 feet. in russia, suspicion remains. here in cairo, no clues yet as to why the plane came down and why 224 people died. back to you, richard. >> just after 8:00 p.m. in cairo. bill neely, thanks for the latest on that. u.s. boots on the ground in syria. secretary of state john kerry says special ops will only fight isis here but will not rule out future u.s. involvement? bill richardson joins us on that. t i really love it. i'm on the move all day long... and sometimes, i just don't eat the way i should. so i drink boost® to get the nutrition that i'm missing. boost complete nutritional drink has 26 essential vitamins and minerals,