Dozens of migrants, mostly toddlers, drown off Libyan coast

"Many of the bodies are small toddlers," tweeted Chris Catrambrone of the non-profit group MOAS, which was helping in the rescue effort.

"Rescuers are frantically trying to break open the locked hold on a wooden boat where hundreds of migrants are trapped!" he tweeted.

"Not a scene from a horror movie... Real life tragedy unfolding on Europe's doorstep today!," he said.

MOAS tweeted photos showing survivors in orange life vests bobbing in Mediterranean waters as they awaited rescue.

"The immediate intervention of the coast guard boat Fiorillo and the MOAS boat Phoenix permitted the rescue of the majority of the migrants who had fallen into the water," the Italian coast guard said in a statement on Wednesday evening.

Earlier in the day, the coastguard said some 200 of 500 migrants aboard fell into the sea, either because a big wave hit the vessel or many migrants suddenly shifted to one side.

In all, 15 relief operations took place on Wednesday, with some 1,800 migrants rescued from unseaworthy dinghies or wooden fishing boats, the Italian coastguard said.

Meanwhile their Libyan counterparts intercepted 237 others, including 20 women and 15 children, travelling on two wooden boats.

The bodies of at least 34 migrants were recovered from the sea off Libya [Getty]

The German charity Jugend Rettet said on Tuesday it had had a run-in with armed men on a boat purportedly commandeered by the Libyan coastguard.

The Libyan boat already had passengers on board - presumably picked up from a dinghy in the area.

Jugend Rettet published a photograph appearing to show the armed men pointing their weapons directly at the migrants and said "a variety of shots" were fired "and refugees were beaten".

About 100 people on the Libyan boat panicked when the shots rang out and threw themselves into the water, swimming towards the German boat Iuventa and the SOS Mediterranee boat Aquarius, which was also at the scene.

"We can not say whether and how many dead there were in the shooting. We had to be careful not to get a bullet ourselves," Jugend Rettet said in a statement citing the Iuventa's 25-year old captain Jonas, without giving his surname.

'Forced us to jump'

SOS Mediterranee said the migrants said the Libyans had ordered them overboard.

"When the Libyans pointed their weapons at us and asked us to give them all our money and our cell phones and told us to jump in the water, we did what they said," a 20-year-old Gambian told the Aquarius crew.

"I was not afraid, I would prefer to die at sea than be forcibly returned and die in Libya," he said.

Two weeks ago, the German NGO Sea-Watch reported an aggressive intervention by the Libyan coastguard as it tried to take control of a large wooden boat sailing in international waters with 450 migrants on board.

The Libyan coastguard has recently begun carrying out its own operations at sea, towing migrant dinghies headed for Europe back to shore and locking up those recovered in centres which are renowned for human rights abuses.

Agencies contributed to this report.