According to the Greek coastguard, at least four migrants perished when their boat became stranded on an islet north of the Greek island of Antikythera on Thursday.
According to official media, 90 migrants are presently stuck on the islet and cannot be removed before early Friday due to terrible weather conditions.
Several coast guard vessels have been dispatched to assist with the search and rescue effort.
The catastrophe occurred the same day when a dinghy carrying migrants sank off the island of Folegandros, killing at least three people.
Thirteen people were recovered, while dozens more are still missing, according to Greek police.
Survivors presented inconsistent reports, with some telling investigators that there were originally 32 people onboard, while others placed the figure closer to 50, according to a coastguard official.
According to the UNHCR, the Folegandros shipwreck was the deadliest in the Aegean Sea this year.
“This shipwreck serves as a heartbreaking reminder that people continue to embark on risky journeys in search of safety,” said Adriano Silvestri, UNHCR’s assistant representative in Greece.
From January through November of this year, the UNHCR estimates that over 2,500 individuals perished or went missing at sea while attempting to reach Europe.
In 2015, about one million individuals, mostly Syrian refugees, entered the EU after crossing to Greek islands near Turkey.