More than 80 refugees are feared dead after a migrant boat sank off the coast of Libya.
An Italian merchant ship rescued 26 people following the disaster but survivors said more than 100 had set sail for Europe on Friday.
The International Organisation for Migration (IOM) said testimonies gathered from asylum seekers taken to safety on the Italian island of Lampedusa indicated that 84 people were missing.
The Italian coast guard said it received a call from a satellite telephone on Friday but heard no voice on the other end.
Rescuers tracked the signal to a location about seven miles off the Libyan coast and diverted a merchant vessel in the area for the rescue.
A spokesperson said they found a sinking rubber boat of the kind that is usually packed with up to 120 people by smugglers.
The closure of land routes through the Balkans and the controversial deal seeing migrants deported back to Turkey from Greece have raised fears that refugees fleeing conflict and persecution will take longer and more dangerous routes to Europe.
The Central Mediterranean route from Libya to Italy has been the deadliest stretch of water for refugees so far this year, seeing more than 900 drown so far.
As of Wednesday, another 370 had died in the Aegean Sea attempting to reach Greece according to the IOM, which puts refugee deaths at more than 1,300 since January.
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