Forestry authorities in Southwest China's Yunnan province have been on high alert over a group of wild elephants that are reported to have been causing chaos in villages.

Early on Tuesday, 14 wild Asian elephants invaded crops in Menghai county, Xishuangbanna Dai autonomous prefecture.

The county's forestry police and forestry bureau sent personnel to warn locals, control traffic and evacuate people to safety, while a drone was used to track the elephants.

Hu Xikai, a forestry police officer, said that the elephants entered the county on Jan 26 and had been wandering through village woods and roadside farmland looking for food.

Three chickens and two geese have been killed after being stepped on by the elephants, which have crossed expressways and eaten crops.

According to the provincial forestry bureau, more than 48,000 cases of wild elephants causing chaos were reported in Yunnan from 2011 to 2015, resulting in 18 deaths, 27 injuries and economic losses of about 99 million yuan ($14.4 million).

Wild Asian elephants are first-class protected animals in China, with their population mainly scattered in Yunnan's Xishuangbanna and in the cities of Pu'er and Lincang.

A lack of food on mountains in winter sometimes forces the elephants to seek food on village farmland.