At least 60 people died on a migrant boat that lost power as it tried to reach Europe from Libya, an aid group said on Thursday, citing accounts from those rescued.
"Survivors report that at least 60 people died en route, including women and at least one child," said Marseille-based SOS Mediterranee.
The group's Ocean Viking rescue ship is currently heading for port, carrying 224 people rescued from different boats.
Among them are 25 from a boat that survivors said had set off from Zawiya, Libya on March 8 – only for its motor to give out three days later.
'Deeply troubled'
UN body the International Organisation for Migration (IOM) said it was "deeply troubled by news of a shipwreck in the Central Mediterranean."
Passengers reported drifting without food or water for several days, said SOS Mediterranee.
It was not immediately clear how those who died were said to have lost their lives. AFP was not in an immediate position to confirm the toll.
Ocean Viking also has aboard 113 people recovered on Wednesday night and a further 88 rescued on Thursday from "an overloaded inflatable craft".
Deadly mission
It has been directed to Ancona on Italy's eastern coast, which SOS Mediterrannee said was 1,450 kilometres (900 miles) from its current position.
The aid group said it had asked Italian authorities for "somewhere closer to put ashore".
SOS Mediterranee has rescued more than 39,000 people in the Mediterranean since 2016 – most of them on the Central Mediterranean route, the world's most dangerous migrant passage.
Last year, 3,105 migrants died or were reported missing attempting to cross the Mediterranean to Europe, according to IOM figures. The count has reached 278 so far this year.
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