A total of 4,340 firefighters are struggling to contain a forest fire in north China's Inner Mongolia Autonomous Region, local authorities said Saturday.

The forest fire in Xiushan, under the jurisdiction of the Jinhe Forestry Bureau in the Greater Hinggan Mountains, raged for three days, according to firefighting headquarters.

After overnight efforts, the fire is basically under control on the eastern and northern fronts.

Steep hills and dense vegetation on the western and southern fronts complicated firefighting, and more firemen are expected to join the efforts.

Local meteorological authorities forecast no significant rainfall and gentle winds between 6 to 19 km per hour in the next few days.

Since June, the Inner Mongolia section of the Greater Hinggan Mountains and its surrounding regions has seen thunder and lightning about 30,000 times. Less rainfall and higher temperatures have also increased the risk of fires.