Singapore was the target of various operations directed by the Allies to disrupt Japan's military activities. On September 26, 1943, a commando unit of the Allied Forces called Z Force, led by Major Ivan Lyon, infiltrated the Port of Singapore, sinking or damaging seven Japanese ships in excess of 39,000 Longtons (40,000 tons). Almost a year later, Lyon commanded another operation, codenamed "Rimau," for the same purpose, sinking three ships. Lyon and 13 of his men were killed in a fight against the Japanese. The other 10 men who participated in the operation were captured, tried in a kangaroo court for espionage, and then executed. Lim Bo Seng of Force 136 commanded another operation, codenamed Gustavus. He recruited and trained hundreds of secret agents through intensive military intelligence activities from China and India. He formed the Special Operations Executive (SOE) Captain John Davis in 1942 with the Chinese-English Guerrilla Task Force 136. Operation Gustav aimed to establish a spy network in Malaya and Singapore to gather information on Japan's activities. Operation Zipper-Codename for their plans to recapture Singapore from the Japanese. Force 136 was finally dissolved after the war.
In August 1945, two Royal Navy XE-class submarines infiltrated the Port of Singapore and participated in a combat battle planned to disrupt Japanese cruiser Takao and Meiko with a limpet mine. They did a lot of damage to Takao and won Lieutenant Ian Edward Fraser of the Victoria Cross. From November 1944 to May 1945, Singapore was exposed to air raids by British and American long-range bombers.
Singapore's naval facilities and piers were bombed 11 times by US air units between November 1944 and May 1945. These attacks did some damage to their targets, but also killed many civilians. However, most Singaporeans welcomed the attack as it was seen as a precursor to Singapore's liberation from Japanese rule.