Well... Robber flies (aka Assassin flies) are all extremely similar and unless you're a trained expert, it's difficult to identify exactly which species it is.
This one is most likely a Neoitamus sp. - red eyes, whitish body, orange and black legs, and tortoiseshell-like back. But it could also be of a Ommatius sp. (most of which have only black at the knuckles, and not lengths of legs). I'm sorry I can't find their common names!
Could you give an estimate of its size? It might help, since Neoitamus at ~2cm is at least half a cm longer than Ommatius.