different threats in a complex story. thank you. a shakeup in security over the boston marathon bombings. catherine herridge is on that story again tonight. one day after homeland security officials confirmed that azamat tazhayakov, a student from kazakhstan was charged with destroying evidence in the boston marathon bombing, a major security change was ordered at the borders. effective immediately, customs agents must verify every foreign student entering the u.s. has a valid student visa. he with drew from classes january 4 and reentered the u.s. two weeks later because customs was never notified of the change. former homeland security officials say policing student visas more than 500,000 issued in 2012, is a chronic problem. the custom border says your visa is expired, now you have to do something with that. who enforces that. there has to be much better cooperation.
today at the madrid people used two fingers to form a lower case b in solidarity with boston. security was beefed up at both the madrid and oklahoma marathons today. and with the anxiety of another attack still fresh in the minds of americans, how might security change at major u.s. events? cnn s nick valencia talked with a security expert. reporter: almost two week since the boston bombings a new gallup poll reports half of americans believe a terrorist attack on the united states could be imminent. 40% worry a family member will be a victim of an attack. with the anxiety of another attack fresh in the minds of americans,t major u.s. events is as relevant a question as ever. and while total security cannot be guaranteed especially in large crowds experts say the risk of an attack can certainly be reduced. it s all about risk management. reporter: director of the national center for spectator sports safety and security since
complacent. mike: claire and marc, stay with us. coming up next, why haven t we heard anything about how the tsarnaevs reported themselves. we ll talk about that. plus, how do we keep our own country safe? how will u.s. security change at major events that happen all the time? stay with us. [ male announcer ] at his current pace, bob will retire when he s 153, which would be fine if bob were a vampire.
complacent. mike: claire and marc, stay with us. coming up next, why haven t we heard anything about how the tsarnaevs reported themselves. we ll talk about that. plus, how do we keep our own country safe? how will u.s. security change at major events that happen all the time? stay with us.
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