A suffocating dust storm is sweeping across western and central Iran on Friday.
The sand particles that are taken by the wind from the deserts in Iraq to the west of Iran have become a regular phenomenon in Iran, especially in the western and southwestern provinces.
Droughts and climate change over the past few decades in the Middle East region have contributed to the growing air pollution from the dust storms coming from the west toward Iran.
The dust storms cause severe air pollution that in turn creates lots of problems for people across different parts of Iran.
Tehran was the most polluted city in the world on Friday as the air quality index rose to nearly 500 on Friday.
The sand particles in the air arrived from the western provinces in Tehran last night.
The health and meteorological officials have asked people to remain indoors amid the severe air pollution while the authorities have yet to announce the closure of schools and offices for tomorrow.
The sand particles are predicted by the meteorological authorities to continue their way toward northern and northeastern provinces in the coming days.
KI