Fears of being hit by space debris forced the crew of the International Space Station (ISS) to go into a docked spaceship for their safety twice on Monday.

The US State Department said the debris was the result of an anti-satellite missile test Russia carried out targeting one of its own satellites, adding there was now an increased risk to astronauts and cosmonauts aboard the ISS as well as other human space flight activities.

"Earlier today, the Russian Federation recklessly conducted a destructive satellite test of a direct ascent anti-satellite missile against one of its own satellites," US State Department spokesman Ned Price said at a briefing.

"The test has so far generated over 1,500 pieces of trackable orbital debris and hundreds of thousands of pieces of smaller orbital debris that now threaten the interests of all nations."

ISS 'in the green zone'

Cosmonaut Piotr Dubrov said the threats were over after the remains of an out-of-service satellite flew by. There were "no signs" of impact, he added.

Anton Shkaplerov, the current ISS commander, tweeted, "Friends, everything is regular with us! We continue to work according to the program." 

There are currently seven crew members aboard the ISS.

Roskosmos, the Russian space agency, confirmed that the station was "in the green zone."

Had the threats been more dangerous, the crew would have had to quickly return to Earth in the Crew Dragon vessel.

US, UK slam Russia's anti-satellite missile test

The State Department said that the danger was far from over. 

"Russia's dangerous and irresponsible behavior jeopardizes the long-term sustainability of outer space and clearly demonstrates that Russia's claims of opposing the weaponization of space are disingenuous and hypocritical," Price said, adding the US would work with allies on a response.

The UK also slammed the Russian anti-satellite missile test, saying that it shows disregard for the security, safety and sustainability of space.

"This destructive anti-satellite missile test by Russia shows a complete disregard for the security, safety and sustainability of space," UK Defense Secretary Wallace said in a post tweeted by the Defense Ministry.

And NASA administrator Bill Nelson said he was "outraged" by the space missile test.

"With its long and storied history in human spaceflight, it is unthinkable that Russia would endanger not only the American and international partner astronauts on the ISS, but also their own cosmonauts" as well as taikonauts aboard the Chinese space station, he said in a statement.

Catastrophic levels of space debris

Such incidents are becoming more common as the skies fill with debris. 

Last week, The New York Times reported that a piece of debris that was spawned by a Chinese anti-satellite weapon test in 2007 forced the ISS to maneuver itself to avoid it on Wednesday.

The US has long warned that the 2007 destruction of a defunct Chinese satellite by a rocket fired from Earth risked creating potentially catastrophic levels of space debris.

sri, fb/aw, jsi (dpa, Interfax, AFP)