This day marked the most disastrous attack by the Japanese on the city. They bombed the Kidderpore dock, killing a large number of people. According to varying estimates, the death toll was between 42 and 500. Most of those killed were labourers.
The Japanese conducted repeated air attacks on the city between December 20 and 28, 1942, which led to damage in Dalhousie Square, Mangoe Lane and Hatibagan. These were night raids.
The Kidderpore raid was the first conducted during the day. The Japanese had flown in undetected with the ground radar having failed to spot them.
According to an account, the Japanese had strategically been air-raiding Chittagong, which forced the Calcutta squadrons to shift from Calcutta. The attack on the dock involved a massive line-up in the sky: 18 Mitsubishi Ki21s, nine Mitsubishi G4Ms and several Nakajima Ki-43 and Mitsubishi A6M Zeros.