Beijing issues highest alert over air pollution

China's capital Beijing has issued its first ever red alert for air pollution, the highest possible warning level. Schools have been advised to stay closed and millions of private cars have been banned from the streets. Al Jazeera's Adrian Brown reports from Beijing. - Subscribe to our channel: http://bit.ly/AJSubscribe - Follow us on Twitter:   / ajenglish   - Find us on Facebook:   / aljazeera   - Check out our website: http://www.aljazeera.com/