Commander Chen Dong and astronauts Liu Yang and Cai Xuzhe touched down in a capsule at a landing site in the Gobi Desert in northern China at around 00:10, according to China Central Television.

Before departing, the astronauts overlapped their stay with that of three other colleagues who arrived on the Shenzhou-15 mission earlier this week for their own six-month stay.

It marked the first time China has had six astronauts in space at the same time.

Medical workers carried the astronauts out of the capsule around 40 minutes after landing, who appeared to be in high spirits as they waved happily at workers at the landing site.

Chen, who was the first to exit the capsule, said: "I am very fortunate to have witnessed the completion of the basic structure of the Chinese space station after six busy and fulfilling months in space.

"Like meteors, we returned to the embrace of the motherland."

Astronaut Liu recalled how moved she was to see relatives and colleagues.

The three astronauts have been part of the Shenzhou-14 mission, which launched in June.

During their time at Tiangong, the astronauts oversaw five rendezvouses and dockings with various spacecraft, including one carrying the third of the station's three modules. 

They also conducted a range of experiments, as well as three spacewalks.

Tiangong is part of China's plans for a permanent human presence in orbit and represents a significant milestone in the country's three-decades-long manned space programme, first approved in 1992.

Weighing around 66 tonnes without attached spacecraft, it could one day be the only space station still up and running if the ISS retires around the end of the decade as expected.

Sky News