During the Japanese occupation of Singapore: Socially, the Japanese imposed their culture through practices like mass drills and making Japanese the primary language in schools and media. They also expanded propaganda to increase loyalty to Japan. Economically, the disruption of Singapore's entreport trade caused widespread food shortages under rationing. Black markets emerged selling goods at high prices. The Japanese devalued local currency. Politically, the Japanese military police enforced order through fear and torture. The Sook Ching massacre targeted thousands of ethnic Chinese. Resistance groups like the Malayan People's Anti-Japanese Army and Force 136 carried out guerilla attacks and spy operations against the Japanese.