Right, he was on a "business" trip to Nepal. Is that why he was hanging around mumbai with an ak47 shooting at people?
Think logically and ask yourself this question. Can bunch of ragtag terrorists coming from sea traveling close to 500 miles on a rubber boat w/o being noticed by Indian security/police can take over a major city in your country? If your answer is yes, than likes of "Ajmal Kasab" are least of your worries.