The NGO says its Sea-Watch 3 boat had headed to the area Friday after its reconnaissance aircraft overheard communications about a rubber boat foundering but were unable to get there in time to help any survivors. Some 117 people are thought to have died in that sinking.
They said Saturday the aircraft reported another rubber boat in distress and Sea-Watch was able to rescue all 47 people on board.
The agency says it hasn't been able to contact Libyan authorities, but has informed both Maltese and Italian officials.
It was not immediately clear where they would take the people rescued. The Italian port of Lampedusa is the closest possibility.
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