The Open arms vessel said it recovered five bodies and that the rickety boat collapsed and tipped them into the sea.
The Spanish NGO managed to distribute waistcoats and masks in the moments before the ground sank.
Several miles away it was a similar situation but on a different boat. Some 13 people drowned off the Libyan coast while it managed to save 85 who were adrift and in danger of sinking in international waters.
Their boat was badly damaged, with water and gasoline spilled inside.
What would have happened to these 88 souls without anyone to help them on the high seas?
As they safely boarded #OpenArms, at least 13 have died in another shipwreck a few miles away.
How many more have to die for justice to be done and all lives equally respected #Med ? pic.twitter.com/hkI0AX9aBr
— Open Arms ENG (@openarms_found) November 10, 2020
The NGO has criticised the fact that the countries of the Mediterranean have abandoned these people and have not moved government relief teams.
Since the start of the year, more than 575 migrants have died while trying to reach Europe, according to the UN’s Migration body the IOM.
The rescue ship set sail from the port of Barcelona (northeast Spain) on November 4 bound for the central Mediterranean, where in recent days it was waiting to receive a request for help.