BEIJING - Heavy fog caused a chain collision of 80 vehicles and left 10 people dead on a highway in south China on Sunday, the Xinhua News Agency reported.

The accident occurred around 8 am outside the city of Nanchang, 1,300 kilometers (800 miles) south of Beijing, and snarled traffic for thousands of vehicles, Xinhua said.

The report did not provide further details on how the pile-up began or whether there were casualties other than the 10 who died.

The accident comes amid China's heaviest travel season, a monthlong period surrounding the Lunar New Year, which begins next Sunday. About 50 million people a day are traveling by long-distance buses for the holiday, Xinhua said, citing the Ministry of Communications.