KUNMING, Feb. 16 (Xinhua) -- An fireworks explosion killed four people and wounded five others Thursday night in southwest China's Yunnan Province, local authorities said Friday.

The accident happened at a fireworks stall at about 11 p.m. Thursday in Tonghai County, according to the county information office.

Two seriously wounded have been taken to hospital in the provincial capital of Kunming.

The cause of the explosion is under investigation.

Though fireworks banis in place in more than 400 Chinese cities, firecrackers are still popular across the country for Spring Festival.