in 1947, the school education law was enacted in japan under the instruction of the supreme commander for the allied forces douglas macarthur. this required all schools in japan to be accredited by the state and made japanese the only official language of instruction. korean could only be used for extracurricular activities. since the ethnic schools did not comply with these regulations, general macarthur instructed that all the korean schools be shut down. as a result of the 1947 school education law, the governor of hyogo prefecture ordered all korean ethnic schools to close down on april 10, 1948. thirteen days later, on april 23, japanese police and military used force to close down schools by physically removing students and nailing the doors shut. the police and military then blocked the entrance to nada and higashi schools to prevent students from entering.