Robber fly? According to my book Asilidae are described as - "Legs are sturdy and have two pads at most." If you look carefully at the sideways image, one leg can clearly be seen to have 3 pads, I think (but I'm not sure what a pad is to be honest - I assume it's the final bits of the legs).
OK so I had another look with a magnifying glass and could only see two hooks/pads on any leg. The photo was lying! Robber fly it is. Thanks