SOS Mediterranée says that the Ocean Viking rescue ship has saved at least 438 migrants in distress on the open seas over the last two days.
According to the Marseille-based NGO, the rescues took place in international waters off the coasts of Libya and Tunisia.
The NGO announced on Thursday it had "rescued 272 people" of 23 different nationalities from three boats in the central Mediterranean, one of the most perilous maritime crossing in the world for migrants.
Those rescued included "32 unaccompanied minors, nine babies and five people with disabilities," according to SOS Mediterranée.
By Friday, the NGO confirmed it had rescued a further 166 people when it "went to the aid of a number of boats in distress."
Those on board were reportedly evacuated "in coordination with the Italian coast guards in the search and rescue area between Tunisia and Lampedusa."
The Italian island of Lampedusa, located just 145 kilometres from Tunisia, is the first port of call for many migrants seeking to make the treacherous sea journey from North Africa to Europe.
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