Schools closed due to severe air pollution in Iran

In Iran, schools in Tehran province have been closed until Friday due to severe air pollution, authorities announced, extending their closure to a full week.

State news agency IRNA reported schools in northern Alborz province were also closed for the week.

Tehran city was cloaked by thick toxic smog for a third successive day today that blanketed out landmarks like Milad Tower and the snow-capped Alborz mountains.

Pollution



worsens in Tehran during winter, when cold air and a lack of wind traps hazardous smog over the capital for days on end, a phenomenon known as thermal inversion.

The sprawling capital is one of the world's most polluted cities.

According to a World Bank report last year, most of the pollution in the city of eight million is caused by heavy duty vehicles, motorbikes, refineries and power plants.