A visitor takes a picture at the Tiananmen Square amid the heavy smog in Beijing, Feb 20, 2014. [Photo/Xinhua]

Beijing issued a yellow alert for heavy pollution on Thursday, due to the heavy smog that had been shrouding the capital since the morning.

It is the first time the city has issued a yellow alert for pollution since the city launched a new alert system in October 2013, because of the city's notorious smoggy days.

The city's environmental protection bureau predicted that the smog will last for three days and suggested the public use public transportation instead of private vehicles to reduce the amount of pollution.

Seniors, especially those with respiratory and lung problems, are advised to take respiratory protections and reduce their outdoor activities, and students of local kindergartens and schools are asked to reduce their outdoor exercise.

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