A traffic policeman signals to drivers during a smoggy day in Harbin, Heilongjiang province, October 21, 2013. The second day of heavy smog with a PM 2.5 index has forced the closure of schools and highways, exceeding 500 micrograms per cubic meter on Monday morning in downtown Harbin, according to Xinhua News Agency. REUTERS/China Daily (CHINA - Tags: ENVIRONMENT TRANSPORT) CHINA OUT. NO COMMERCIAL OR EDITORIAL SALES IN CHINA - RTX14IFX
