Updated 5.14 pm

CREW MEMBERS HAVE been evacuated from the US section of the International Space Station after an alert sounded that could indicate a dangerous ammonia leak.

The six-member crew donned emergency masks and hurried to the Russian side of the orbiting lab after the alert, closing the hatch to the US side behind them.

While the Russian space agency told news outlets in Moscow that the cause was a toxic leak, NASA said there was no data to confirm that, and stressed that the crew was safe.

“Big picture perspective, we are still trying to figure out exactly what happened. We are not entirely convinced that this is an ammonia leak,” Kelly said.

Ammonia is used in the cooling and heating systems at the orbiting outpost.

A sensor problem or a computer relay issue could have led to the alarm, Kelly added.

“It is becoming a stronger case that this is a false indication, which is great news,” he said.

The six astronauts taking shelter in the Russian segment have enough food for at least a week, NASA said.

News of the evacuation was first released by Maksim Matyushin , the head of the Russian Mission Control Center:

The safety of the crew has been secured by prompt joint action by the US and Russian crew members, as well as by mission control staff in Moscow and Houston.

© – AFP 2015 with reporting from Rónán Duffy

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