A herd of 15 wild elephants on Wednesday was approaching the city of Kunming, the capital of southwest China's Yunnan province.

The group of Asian elephants, which includes three calves, have reportedly trekked for nearly 500 kilometers (300 miles) along highways and through fields of crops over the past months.

According to the Chinese state-run news agency, Xinhua, the herd on Wednesday was in Yuxi, about 20 kilometers (12 miles) from Kunming, a city of 7 million people.

While the elephants crossed the road, authorities blocked traffic, set up barriers and used food as bait to keep them away from populated areas.

The damage they caused to farmland is estimated at 6.8 million yuan ($1.1 million), according to Xinhua.

Herd leader 'lacks experience'

Chen Mingyong, an Asian elephant expert cited by Xinhua, said the incident was the longest-distance migration of wild elephants recorded in China. Chen said it was possible their leader "lacks experience and led the whole group astray.''

Wildlife authorities say it is unclear why the herd left a nature reserve last year near the city of Pu'er, a region known for tea cultivation. But the Xinhua report suggested that a decline in edible plants in forest habitats might have triggered their move.

Last week, the elephants wandered the streets of the town of Eshan for six hours after residents were warned to stay indoors, Xinhua reported.

Some fear that conflicts might arise between villagers and elephants as they enter villages and eat crops.

According to Xinhua, a task force of 360 people with 76 cars and nine drones was tracking the elephants.

The wild animals are a protected species in China. 

fb/aw (AP, Reuters)