At least 100 migrants on board a raft travelling from Libya, and thought to be destined for the Italian coast, have been picked up by the Italian coast guard after venturing into force-seven seas with waves up to eight-metres high.

The Italian coast guard confirmed that 29 people had died.

Al Jazeera's Claudio Lavanga, reporting from Rome said that the coast guards saw the migrants trapped in waves of up to eight metres high and weather conditions as low a zero degrees Celcius.

"The coast guard says that by the time they got there seven people were already dead but that 22 more people died due to hypothermia on the rescue boat on the long journey back to the island of Lampedusa," he said.

The migrants had summoned help via satellite telephone 160km off the coast of the southern Italian island of Lampedusa.

Two Italian coast guard rescue boats which were due to land on Lampedusa, south of Sicily, on Monday, were initially delayed by bad weather conditions in the Strait of Sicily, between Sicily and Tunisia.

Coast guard commander Filippo Marini said on Monday that 105 migrants were aboard an inflatable life raft who were trying to cross the Mediterranean.

"We have six young people in a critical hypothermic state in our centre and we are trying to evacuate them to a better equipped hospital," a doctor on the island of Lampedusa told the AFP news agency.


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Al Jazeera's Lavanga said that the incident was bound to reignite criticism toward the Italian government decision to end Mare Nostrum.

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The operation deployed a fleet of airplanes, helicopters and vessels to intercept migrant boats before they run into trouble throughout 2014 and which is accredited for having saved at least a 150,000 migrants, he said.

"This operation was replaced by a European Union's Frontex-led Operation Triton, which critics say is not a rescue operation, but rather a border operation.

"They say that boats cannot rescue migrants until they receive a distress signal, which like in Monday's case, may be too late," said Lavanga. 

Since the beginning of 2014, more than 150,000 migrants have arrived in Italy on unseaworthy boats, many refugees of war and conflict.

More than 3,200 people have died in the last year, attempting to reach Italy by boat from North Africa. 

Recent increasing violence in Libya has forced people to flee the country which is mired in the worst fighting since former leader Muammar Gaddafi was overthrown.

Source: Al Jazeera and agencies