A few days previously their commanding officer, Colonel Goubard, had reported to the Commander-in-Chief, General Ailleret, that his Tirailleurs — averaging twenty years of age and with only eighteen months’ training — had proved themselves in the djebel but were in no way conditioned or trained for police activities in the city. … Suddenly shots were fired by an unknown hand from a rooftop on the Rue d’Isly. The young Tirailleurs began spontaneously to shoot back, as they would have done out in the djebel. They shot, and shot — wildly, and at point-blank range — into the crowd. … When the shooting was finally stopped, forty-six dead and 200 wounded were picked up, more than a score of whom died subsequently. Afterwards some 2,000 cartridge cases were counted. Lengthy enquiries were held but, although the identity of the sniper on the roof was never clarified, it was generally assumed that he had belonged to the O.A.S., aiming deliberately to provoke a massacre that would speed the breakdown of order in Algiers.

QUESTION: The sniper's identity was never confirmed; is there more historical evidence about who fired from the rooftop?

Horne, Alistair, A Savage War of Peace- Alge…, loc. 1604