18-year-old girl dead. what is your read on this that authorities have arrest ed a 23-year-old man in addition to the apparent suicide bomber? >> well, you know, i think it's probably a bigger sail. this was a well-planned attack. the suicide bomber didn't enter the arena. he didn't have to go through security. he was placed where he would cause the maximum damage in a suicide vest like that. 22 people is probably the maximum damage you can do. these bombs, homemade bombs, have to be very carefully delivered. if it was acetone and peroxide it has to be cooled, and i could go on and on, which suggests that somebody knew what they were doing. these bombs are easy to make, but you still need supervision, and i would expect an arrest and maybe more. i think we're dealing with a cell. the british police are worried about add-on attacks right now, and they're doing everything they can to stop them. >> julia cayenne, as we see the