This type of street (or plaza) photography requires pre-planning, dexterity, and a little luck. The pre-planning here was mostly successful. The lone man on the distant bench is interesting, as is the foreground tree as a framing element, though the bark is over-exposed (but mostly this can be easily cropped). The luck part is the confluence of the two sets of figures, the worker and the two police/military men. Better had there been more separation of the pair from the bench, which would have required dexterity to shift your shooting angle a bit to the left. A good technique to accomplish all this is to prefocus and compose, but to keep your eyes free from the viewfinder so that you can quickly shift the camera position to accurately capture the separation of the moving figures within the desired composition.
Il contrasto mi sembra un pò troppo forte, almeno sull'albero frontale... La composizione é molto equilibrata e il movimento tende tutto a indirizzare l'occhio verso destra, quindi ottimo per poi tornare sul soggetto principale, che credo sia l'uomo con il turbante.