At least 110 migrants are feared drowned after they were forced at gunpoint to set sail from Libya, while many more may have died in a separate shipwreck, survivors said Thursday.
"A vessel with around 140 people on board overturned Wednesday just a few hours after setting off from Libya, throwing everyone into the water. Only 29 people survived," UNHCR spokeswoman Carlotta Sami told AFP.
The Norwegian Siem Pilot was first on the scene, around 20 nautical miles off Libya, and rescued the survivors — all in a poor condition after hours in the water — with the help of four other vessels. Twelve bodies were recovered.
In a possible second incident, which could not be confirmed by the coast guard, two women told the UN agency they believed they were the only survivors in an disaster in which some 125 people drowned.
"They told us they were on a faulty dinghy which began to sank as soon as they set sail. They were the only survivors," Sami said.
Those pulled to safety were transferred to Lampedusa by the Italian coast guard, where they told aid workers and the island's doctor how they had set off from Libya in rough seas.
"Their tales are horrifying," doctor Pietro Bartolo told Italian television network Tv2000.
Once the migrants had realised they were being put out to sea in bad weather, they tried to turn back, but were forced on at gunpoint.
"To make them get on the dinghies they (the traffickers) shot a man, killing him dead. They made them depart and after a few miles at sea the tragedy happened," Bartolo said.
"One woman said she had to hold on to a dead body to survive. They said they spent many hours in the water in the hope someone would save them. But when the rescuers arrived there was nothing to be done for most of them," he added.
The latest tragedy brings the number of migrants who have died or are missing feared drowned this year to over 4,000.
"Another tragedy on the high seas, with 239 feared dead in the Mediterranean, once again. So many lives could be saved through more resettlement and legal pathways to protection," said the UN's refugee chief Filippo Grandi.
Sami, the spokeswoman, tweeted: "One in every 42 people are dying in the Central Mediterranean looking for safety".
The rescue situation is often chaotic, with people confused, sick or exhausted after periods in crisis-hit Libya unable to specify how many people were on board their dinghies at the outset or what vessel pulled them from the water.
Around 750 migrants were rescued across the Mediterranean on Thursday by the Italian coast guard, a Frontex ship, a Save the Children vessel, German NGO Jugend Rettet's Iuventa and two boats run by the Malta-based MOAS (Migrant Offshore Aid Station).
MOAS's Topaz Responder plucked close to 180 people from the water, according to an AFP photographer on board.
"The (Responder ) crew was shouting at them to sit down and stay calm while the life jackets were handed out but they were getting agitated, and around 10 of them fell overboard, some without life jackets on," photographer Andreas Solaro said.
October marked a record monthly high in the number of migrants arriving in Italy in recent years — some 27,000 people — and the departures have showed no sign of slowing, despite worsening weather in the Mediterranean.
Amnesty International warned Thursday the pressure placed on Italy by Europe to cope alone with the worst migration crisis since World War II had led to "unlawful expulsions and ill-treatment which in some cases may amount to torture".
The report was bluntly rejected by Italy's chief of police, who denied the use of violent methods in the force's handling of migrants.
