On the night of August 24, a formation of German bombers meant to attack aircraft factories and an oil depot east of London lost its bearings and flew over London itself. The RAF tracked the bombers from France, but Britain still lacked an effective system for stopping intruders at night. Radar plotting was too slow and imprecise, pilots had to see targets to attack, and experimental night-fighting methods, including airborne radar, had not yet worked well. British defenses also included barrage balloons, searchlights, anti-aircraft guns, and efforts to jam or distort German navigational beams, but these measures were only partly effective.

As the bombers approached, air-raid sirens sounded across London. CBS reporter Edward R. Murrow began broadcasting live from Trafalgar Square, describing the sirens, searchlights, dimmed traffic signals, buses moving through blackout conditions, and the eerie sound of footsteps in the dark. While Murrow did not witness explosions from his position, bombs soon began falling farther east in central London, hitting areas including Stepney, Finsbury, Tottenham, Bethnal Green, and the vicinity of St. Giles’s Church in Cripplegate.

The physical damage was limited and casualties were few, but the raid deeply unsettled Londoners because it seemed to announce a dangerous new stage of the war. At the time, people in Britain did not know the bombs had been dropped by mistake or that Hitler had forbidden attacks on London. Göring angrily demanded to know which crews had bombed the prohibited zone and threatened to punish their commanders severely. Mass-Observation diarist Olivia Cockett recorded the psychological effect of the raid, imagining collapsing services, poison, and endless catastrophe, and describing how ordinary sounds now triggered fear.

For Churchill, the mistaken bombing of London was both enraging and useful. He had been frustrated that British bombing of German industrial and military targets had done little to hurt Germany or impress the enemy psychologically. The attack on London now gave Churchill the moral justification he had wanted to order a retaliatory strike on Berlin, pushing the air war toward a more direct escalation.