A forest fire that broke out on Wednesday in the outskirts of Kunming, capital of Southwest China's Yunnan Province, is still blazing southwards, despite efforts to stop the fire spreading, authorities said on Friday.

The Kunming Forest Fire Prevention Headquarters said 4,700 people have been mobilized for the firefighting, which has been aided with four helicopters dropping water on the flames.

A spokesman with the headquarters said they plan to dig a ditch to prevent the fire from spreading further southwards.

About 130 people were evacuated from the area on Thursday.

No casualties have been reported, after the blaze was first spotted in Lizhe Village of Xishan district at 3:20 pm on Wednesday.

The cause of the fire is under investigation.