At least 250 refugees are feared dead after shipwrecks in the Mediterranean, according to the United Nations.
Two partially submerged rubber dinghies were found in open water, around 30km north of the Libyan port of Sabratha.
Laura Lanuza, from Spanish NGO Proactiva Open Arms, said each vessel had capacity for up to 140 people.
She added that five bodies were recovered on Thursday (May 4), all of them African men aged between 16 and 25. She said they had drowned in the 24 hours prior to their discovery.
"We don't think there can be any other explanation than that these dinghies would have been full of people," Lanuza told AFP news agency.
Meanwhile the UNHCR has reported a further two shipwrecks, off the coasts of Libya and Italy.
Although 50 people were rescued and disembarked in Pozzallo, Sicily, on Sunday, the remaining 82 are feared to have drowned.
The second shipwreck took place off the coast of Libya. Although the International Medical Corps claims a total of seven people were rescued by the Libyan Coast Guard, a further 163 people are feared unaccounted for.
The migrant crisis continues to claim huge amounts of lives as refugees and asylum seekers risk their lives crossing the sea to Europe in dinghies and flimsy boats.
From January 1 to March 9 this year, at least 521 people drowned in this attempt - an increase of 50 from the first nine months of 2016.