Transcript for The Race Against the Clock
Martha Raddatz -- on the phone with sources today just back from Boston Martha. So presumably they are looking at surveillance tapes in this area what do you know about that when you heard Brian say there is tons of video they've got surveillance. Everywhere in that area it was the Boston Marathon of course they had a lot of cameras out there. And you have social media you have cell phone video that's why they're asking for all this. The hard part here though Dianne is the more you have. The longer it takes to go through it the more people you need to go through it the more experts you need. And meanwhile. This bomber this terrorist or terrorists are trying to get away any other sense about how long this investigation could be going on and done. -- investigations in the past have had breaks in the Oklahoma City bombing they made a mistake and they got caught within ninety minutes the World Trade Center bombing in 1993. They made a mistake. But they caught those people very very quickly. This one will -- -- -- 24 hours now and time is really critical here in order to get someone they may solve this crime. But someone may be getting away right. -- thank you my and there is one more thing we think we know about this bomber he may have studied last year's race. To pinpoint the moment of maximum runners crossing the finish line. The maximum crowd for hours and eighteen minutes in and that's almost exactly. The time his bombs exploded.
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