A leak was detected aboard the International Space Station Wednesday night, but NASA said it was "minute" and posed no threat to the astronauts now aboard the station. "The crew is in no danger and is actively working troubleshooting procedures," the space agency said in a tweet.

The leak was detected around 7 p.m. EDT by flight controllers in Houston and Moscow. The controllers chose not to wake the astronauts, who were asleep at the time. This morning the astronauts gathered in the station's Russian segment, which is believed to be the source of the leak.

NASA gave no details on the cause of the leak, but the head of Russia's State Space Corporation, Dmitry Rogozin, told the Russian news agency Tass that it appeared to be in a side compartment of the Soyuz space capsule attached the the station.

"A micro-fracture was found," Rogozin said. "Most likely this is external damage. Designers believe this is the result of a micro-meteorite."

Rogozin said the leak could be repaired from within, with no need for a spacewalk.

Six astronauts are currently aboard the station: Drew Feustel, Ricky Arnold and Serena Auñón-Chancellor of NASA: Alexander Gerst of the European Space Agency; and Russian cosmonauts Oleg Artemyev and Sergey Prokopyev.

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