Firefighters continue their rescue operation after successfully saving 16 trapped residents who lived in a building that caught fire after a gas leak that led to a strong explosion in Puyang city, Henan province on Friday morning, November 20, 2009. [Photo: chinanews.com.cn]

A residential building in Puyang city, central China's Henan province, caught fire on Friday morning after a gas leak that led to a strong explosion, China News Service reports.

So far, 16 local residents who were trapped by the fire have been successfully rescued.

Further rescue works are still underway among the debris of the collapsed first three floors of the building. The exact number of casualties is unknown yet.