Shortly after taking off from Baikonur Cosmodrome in Kazakhstan, Nick Hague and Alexey Ovchinin reported a problem with the rocket’s booster.

The men were forced into a “ballistic descent”, with their capsule landing a few hundred miles north of Baikonur.

They have been picked up by rescuers.

“The search and recovery teams have reached the Soyuz spacecraft landing site and report that the two crew members… are in good condition and are out of the capsule,” US space agency Nasa said.

Russia said it was suspending any further manned flights, and an investigation into what went wrong had begun.

What happened to the rocket?

The launch appeared to be going smoothly, but some 90 seconds later Nasa, on its livestream, reported that a problem seemed to have occurred with the booster rocket between the first and second stages of separation.

Footage from inside the capsule showed the two men being shaken around at the moment that the fault happened.

Shortly afterwards, Nasa said they were making a “ballistic descent” meaning their capsule descended at a much sharper angle than normal and would have been subjected to greater G-force – the force imposed on a body by rapid acceleration.

The capsule separated from the failing rocket and later deployed parachutes to slow its descent.