Astronauts return to ISS after sheltering during air leak repair attempt

Astronauts on the International Space Station (ISS) were ordered to shelter in an attached spacecraft after the structure suddenly started leaking more air.

Five of the seven crew were directed to go into the docked SpaceX shuttle Dragon "Freedom" on Friday afternoon and were braced for a potential evacuation.

Meanwhile, two remaining personnel - a pair of Russian cosmonauts - attempted to repair a part of the Russian segment of the ISS, where the leaks had started increasing on Monday.

The repairs were paused and the crew ordered back onto the ISS by Nasa on Friday afternoon.

Jessica Meir, Jack Hathaway, Sophie Adenot and Andrey Fedyaev, who arrived on the ISS in February, had been sheltering on the docked ship, along with another astronaut Chris Williams.

They had been told to put on their spacesuits so they were ready to undock and return to Earth at short notice.

The Dragon effectively functions as a lifeboat - attached to the station but ready to detach the moment the order is given.

The trigger for the order was a worsening air leak in the transfer tunnel, known as PrK, leading to a section of the Russian segment of the station called the Zvezda service module.