The Mehr news agency, owned by the Office of the Supreme Leader Ayatollah Ali Khamenei, on Tuesday quoted Brigadier General Hossein Sajjedi-Nia, a senior Tehran police official, as suggesting that schools remain closed on Thursday as well.
Tehrans Air Quality Control Company (AQCC) said that the Pollutant Standard Index (PSI) in the capital had remained around about 160 for the past several days.
The report advised elderly people with heart or breathing problems and young children from staying in the open air, particularly where there was heavy traffic.
The advisory cited dangerous levels of carbon monoxide in the atmosphere.
Tehran is one of the most polluted cities in the world. Earlier this year, officials announced that air pollution in the capital had increased to more than 200 PSI (Pollutant Standards Index) and would top the 233 PSI mark in certain districts. Pollution levels generally fall between 0 to 100 PSI.
Many experts blame the government of not regulating harmful gas emissions by the industrial sector.
In a separate dispatch Monday evening, Mehr said that all schools and universities would be shut until Wednesday evening.
In its website the AQCC said that 160 PSI represented unhealthy air pollution levels. It is rare, however, for learning institutions to be closed down for such levels of air pollution.
Wednesday marks Students Day in Iran. Student protests have been on the rise in Iran in recent weeks in the run-up to the anniversary of the bloody suppression of a rally outside Tehran University in 1953.
On December 7, 1953, three students were shot dead by policemen during a rally against the Shahs dictatorship. The day has been named Students Day and commemorated on campuses across Iran every year.
