Is it possible for MSc (India) student to pursue MS in US? Is it possible for an Indian student with M.Sc degree to do M.S course in USA? I heard BS degree in USA is of 4 years, but in India MSc is done after BSc.
So long as you meet or exceed (but not by too much!) the graduate admission requirements of a department, there's no reason you shouldn't be able to study there. There's no fixed rule that says that you can't do a master's in India then do one in the US as well. (If there is such a rule, it applies only to the departments or universities that impose them; there are no universal rules that govern US graduate admissions.)

The best bet is, of course, to contact the schools you're interest in attending and ask them directly what their policies are.