Beijing (AP) — Elephants in a wandering herd in southwest China walked down paved roads and poked their trunks through windows as they neared a city and authorities rushed to protect both the animals and people.

It’s not clear why the 15 elephants made their long trek from a nature reserve which has been documented and monitored both on the ground and from the air by a dozen drones. Authorities have urged people in the area to stay indoors and are blocking roads with construction equipment while seeking to lure the animals away with food.

The elephants have already walked 500 kilometers (300 miles) from the reserve in Yunnan’s mountainous southwest. They appear healthy in images showing them roaming through farmland, villages and down paved roads at night in urban areas.

One city along their route, Yuxi, deployed hundreds of trucks along a road to discourage the herd from approaching, the Beijing News reported. Drivers ate and slept in the vehicles for days, even as they heard the elephants moving about after dark, the newspaper said in a video clip posted online.

On Tuesday, they turned up at a retirement home and poked their trunks into some of the rooms, prompting one elderly man to hide under his bed, according to residents interviewed by online channel Jimu News.

The Xinhua News Agency reported Thursday that the herd by late Wednesday night had reached the Jinning district on the edge of Kunming, a city of 7 million people that is the capital of Yunnan province.

The government of the semi-rural district issued a notice urging residents not to leave corn or other food out in their yards that might attract the animals and to avoid contact with them.

It was “forbidden to surround and gawk at the elephants” or to disturb them by using firecrackers or other materials, the notice said.

Sixteen animals were originally in the group, but the government says two returned home and a baby was born during the walk. The herd is now composed of six female and three male adults, three juveniles and three calves, according to official reports.

No injuries have been reported, but reports say the elephants have damaged or destroyed more than $1 million worth of crops.

When and how the elephants will be returned to the reserve isn’t clear. Elephants are the largest land animals in Asia and can weigh up to 5 tons.