HOHHOT - More than 200 fire fighters from north China's Inner Mongolia Autonomous Region are Monday battling a grassland fire that crossed the Sino-Mongolian border into China.

According to regional forest police, it will be difficult to extinguish the blaze which crossed border on Thursday and has raged in New Barag Left Banner near the city of Hulunbuir for several days.

A heat wave has affected north China including Inner Mongolia since last week. Owing to high temperatures, an ongoing drought, and strong winds, the blaze has spread quickly.

No casualties have been reported in China. The burned area and economic loss are being calculated.