On 22 February five postmen were shot down with careful selectivity: two Europeans, two Muslims, one Jew. Henceforth the mail was no longer delivered. Next the O.A.S. singled out the pharmacists, Muslim and European, on suspicion that some of them were aiding the F.L.N. Then came the tram-workers and railwaymen, employees of Algiers Electricity and Gas, the coiffeuses and the doctors; finally the wretched flower-vendors, shot down at street corners among the pathetic debris of their carnations and roses. On 24 February, following the killing by the F.L.N. of a Bab-el-Oued taxi-driver, a pied noir mob trapped a score of Muslim workers in a cul-de-sac and stabbed and beat them to death. Increasingly, a kind of apartheid, which had never previously existed, was growing up in the cities as Muslim workers declined to enter the European quarters - and vice versa.
Alistair Horne, A Savage War of Peace: Algeria 1954-1962.