SHIJIAZHUANG - More than 2,000 people are struggling to put out a forest fire that has been raging on a mountain to the northeast of Beijing, local authorities said Tuesday.

Steep hills, strong winds and poor telecommunications have added difficulty to efforts to control the blaze, which started on a mountain in Chengde city, Hebei province, at about 1 pm Monday, according to a spokesman for provincial forest fire control authorities.

The cause of the fire remains unclear, he said.

Vice-provincial governor Shen Xiaoping has arrived at the site, less than 200 km away from Beijing, to oversee the operation.