Around 270 people are now on board the group’s Sea-Watch 3 ship after the latest rescue, the Berlin-based group said on Saturday.

The crew had reached its area of operation in the central Mediterranean only on Thursday.

Shortly afterwards, it rescued a group of migrants in distress who were in international waters south of the Italian island of Lampedusa.

The migrants’ boats, which are often unseaworthy and prone to sinking, frequently head for Lampedusa because of its proximity to the coast of North Africa.

According to government figures, about 47 per cent more migrants have arrived in boats in Italy so far this year than in the same period last year.

The private rescue operations like Sea-Watch are politically controversial, with critics saying they are effectively aiding people smugglers.

The organizations say they abide by international law and argue that the European Union has failed to protect these desperate people who are in search of a better life.