I went to my balcony for smoking. meanwhile i saw a light blinking. at first i thought it was a star.Then i saw it moving.Then i heard a strange sound which was not similar to any other vehicle such as a plane or jet or anything else.The sound was increasing and decreasing.And it was moving really fast.Then i rushed to the other balcony on the same direction. but there was nothing there. any vehicle could not move that fast or change its direction or make this sort of sound. i opened google earth and saw nothing. then i reported the incident here.