Booster rockets carrying a Soyuz spacecraft with a Russian and a US astronaut on board headed for the International Space Station failed mid-air on Thursday, forcing the crew to make an emergency landing.

NASA said that the crew was safe and was making an emergency landing in Kazakhstan where the unsuccessful launch took place.

"The crew is returning to Earth in a ballistic descent mode," wrote NASA, noting that the descent would take place at a steeper angle than usual, but that rescue crews were en route to the expected scene of the landing.

Both crew members are safe and in good condition, and have been retrieved from the Soyuz booster. 

Earlier:

The crew remains in good condition and in touch with ground rescue teams, according to NASA.

International groups of astronauts often accompany each other to the International Space Station in joint launches.

This article was originally published by Business Insider.

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