Nature World: Beijing raised its pollution alert a notch higher Friday, in a bid to improve air quality levels. The capital issued a rare "orange" alert, the second-highest level possible.
The Chinese capital expects heavy smog to linger in the city for the next three days. Young children and the elderly have been asked to stay indoors.
Beijing currently has a four-tier alert system, which uses blue, yellow, orange and red to indicate the levels of air pollution, according to Xinhua's earlier report.
The...