whoa slow down there bud. A thousand clones is a HUGE stretch. Naruto used 2,oo0 clones to fight garra and he was being pushed to the limit and had some Kyubbi chakra and extra training. He can make a hundred max. He did not have a lot of clones and plus he does not have any kyubbi chakra
Bridge is tots destroyed. Their tech is not on our level and it was not even complete 2 weeks away from competition. The blast may also hurt teammates. The clones can barley move. Of bridge breaks than gennin would fall in.