There are special schools named "Chosen-gakkou"（朝鮮学校） in Japan. The ancestors of students are Korean who were taken to Japan mainly from the northern part of Korean peninsula where now is North Korea.
There is also "Chosen-gakkou" in Orio（折尾） area where is next to my town. In the past, especially when I went to high school, I used to often see many female students wearing "Chima-jeogori" styled uniforms. But, now we cannot find them. Why?
Because, now they have been wearing same blazer styled uniforms that are used in many high school in Japan. In other words, we cannot recognize whether they belong "Chosen-gakkou" or not, by their uniforms.
Several years ago, some abuse incidents against "Chosen-gakkou" students had happened in Japan. I think that they have stopped using their traditonal uniforms to avoid that bad situation. It is sad thing, but fact.