3 January 2005 -- The Iranian government yesterday closed down all kindergartens, primary, and junior high schools in Tehran after air pollution reached critical levels.
IRIB state television urged elderly people, especially those with cardiac problems, to stay home.
Many residents in downtown Tehran wore masks to protect themselves from severe pollution which blocked the view of the Elburz Mountains in the north.
IRIB announced a relaxation of the measures at noon yesterday as pollution levels had dropped after people followed municipal recommendations to use only public transportation means.
Tehran, which is 900 square kilometres in size, is one of the world's most polluted cities.