A herd of elephants that have been tracked as they travelled nearly 500km across China were spotted taking a quick break for a group nap in a forest near the city of Kunming.

Drone footage released by Chinese state media yesterday shows the herd, including a young calf, taking a rest.

The footage, shot on Monday 7 June by a drone operated by officials from the Yunnan Forest Firefighting Brigade, shows the herd of 15 elephants sleeping in a forested area of Kunming, the capital of Yunnan province, state broadcaster CCTV reported.

The group of Asian elephants, which includes three calves, originally lived in a nature reserve, according to the official Xinhua news agency.

They have trekked for nearly 500 km along highways and through fields of crops over the past months.

The herd reached Kunming last week, defying authorities' attempts to redirect them.

The elephants have been under constant surveillance from authorities since heading north, who have even deployed heat-seeking drones to keep track of the animals.

While it is unclear why the elephants are moving north, the Xinhua report said a decline in edible plants in forest habitats has put pressure on the animals, whose numbers have grown in Yunnan in recent decades.