Through clouds of smoke, two black-clad and face-masked central security troops advance steadily towards the camera, pausing every few seconds to fire shotgun rounds that whistle perilously close to the screen.

On one side of the street is a column of armed riot police; on the other, hundreds of stone-throwing youths, their heads wrapped in scarves, bodies occasionally crumpling to the floor as another volley is fired.

And in the middle of it all stands the cameraman, Mostafa Bahgat.