The sky over Seoul is covered in fine dust, as seen from the South Gate Observatory of Namhansanseong Fortress in Gwangju on Tuesday. (Yonhap)
The sky over Seoul is covered in fine dust, as seen from the South Gate Observatory of Namhansanseong Fortress in Gwangju on Tuesday. (Yonhap)

Visibility is reduced as heavy fine dust engulfs Seoul, obscuring the view of Lotte World Tower in southern Seoul on Tuesday. (Yonhap)
Visibility is reduced as heavy fine dust engulfs Seoul, obscuring the view of Lotte World Tower in southern Seoul on Tuesday. (Yonhap)