volgograd blast. they're not really a corporate structure. they're separate cells, often very young, a lot younger than some of the militants we've seen in the past decade, often in their early 20s. the oldest ones get to 30 before they're killed by russian special forces, but they're the ones with the radical ideology, organization, and in cases the sheer will to die in cases like these. we've seen people who sought the culture, sought the fundamentalist underground that they provide and possibly if you see some of the more recent acts they've done, the bombmaking seems to be a little more sophisticated. possibly this may be with where the concerns are emfa naturing from. >> nick paton walsh on the ground in sochi. ivan watson watching what's going on as well. thanks to both of you for your excellent eyewitness accounts for what is going on. that's it for me. thanks very much for watch. "crossfire" starts right now. >> this is cnn breaking news.