The previous day, Friday, January 25, in a major clash in the Suez Canal Zone, the British Army had killed 50 Egyptian policemen in Ismailia after besieging the police post following hit-and-run attacks on British troops. (For details, including a video, see this post.) The Wafd Government of Prime Minister Mustafa Nahas had previously abrogated the Anglo-Egyptian Treaty of 1936, and Interior Minister Fuad Serag al-Din ordered the police to hold out at all costs.
When demonstrators saw a police officer dining with a woman on the terrace of Casino Opera, the famed nightclub founded by Badia Masabni on Opera Square, they attacked him for not joining his colleagues in Ismailia, and proceeded to sack and burn the club, Cairo's most famous belly-dancing venue. (Badia Masabni had sold the club in 1950 but most still called it Madame Badia's.) That is usually considered the first of the fires, and may have been the Brotherhood, which opposed nightclubs, bars, and cinemas, all of which were soon being targeted.
As the afternoon wore on, mobs (some apparently organized, some not) attacked British institutions (most famously Shepheard's Hotel, but also Barclay's Bank, the Turf Club, etc.); institutions owned by Greeks, Italians, Jews and others were also targeted.
|Shepheard's in Ruins|
|Cinema Rivoli on fire|
|Cicurel Department Store|
A newsreel of the aftermath: