Smoggy days arrive early in northeastern regions

Extreme air pollution levels measured in Harbin; haze to linger elsewhere

As coal-burning heat systems came alive in mid-October in Northeast China's Heilongjiang province, the smog that usually waits for late autumn and winter came early.

Meteorological authorities in the province issued an orange alert for heavy air pollution on Wednesday, the second-highest alert in the nation's four-tier emergency response system.