Eleven migrants have died and nearly 200 are missing after two boats sank off the coast of Libya, UN agencies said on Monday citing survivors, in the latest such tragedy.
The first involved an inflatable craft which left Libya early on Friday with 132 people on board, only to start deflating a few hours later, before overturning.
Then on Sunday seven migrants — who said they had been on a boat packed with 170 migrants — were rescued by Libyan fishermen and coast guards off the coast of the Libyan capital.
International Medical Corps, which gave medical care to the survivors, also confirmed their account.
About 7,500 people have been rescued off the coast of Libya since Thursday, Italian and Libyan coast guards said.
Two groups of survivors told the organisations that hundreds drowned when their rubber boats began to deflate before rescuers arrived.
There was some discrepancy in the numbers. Based on its interviews with some of the survivors in Pozzallo, Italy, the UN refugee agency estimated the number of dead at more than 80.
The UN refugee agency says that, excluding the latest shipwrecks, more than 1,150 people have disappeared or died so far this year trying to reach Italy from North Africa, where a breakdown of law and order has allowed people smugglers to operate with impunity.
The number of people leaving Libya in the hope of starting a new life in Europe is up nearly 50 percent this year compared with the opening months of 2016.
"The increasing numbers of passengers on board vessels used by traffickers, with an average of 100 to 150 people, are alarming and the main cause of shipwrecks," United Nations High Commissioner for Refugees Filippo Grandi said on Sunday.
Risks are increased by the worsening quality of vessels and the increasing use of rubber boats instead of wooden ones.