Leaning in desperation over the side of a packed boat, one man grabs the hand of a tiny baby being held aloft from the water by another.

This was the horrific scene in the Mediterranean, where 11,000 migrants have been rescued so far this week.

Some 4,655 people were saved 12 miles off the Libyan coast on Tuesday, including four pregnant women who gave birth on their way to Italian ports.

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Migrants try to pull a child out of the water (centre) as they wait to be rescued off the coast of Libya

Calm seas have encouraged a fresh influx of migrants rushing to cross from North Africa to Europe before winter.

Rescue workers spent hours trying to save 1,000 people on board one boat on Tuesday.

Hundreds of mainly African migrants were hauled to safety, but dozens died in agony from suffocation.

A young child is held aloft on a boat surrounded by migrants travelling between Libya and Italy

Once inside the boat, rescuers found the bodies of more than two dozen people among discarded clothes, shoes and blankets. As darkness fell, they used stretchers to lift the corpses up from the vessel’s hold.

On an inflatable dinghy where the dead were piled up, survivors had to step over the bodies on their way to safety.

In the water, an African man could be seen clinging desperately to a float while trying to stretch his leg out to help a fellow passenger floundering a yard away from him. Many small children were among those crowded on the boats.

Italy's coastguard has said it carried out 33 separate rescue operations on Tuesday, with calm seas blamed for the number of people making the dangerous journey

Italy’s coastguard said it carried out 33 separate rescue operations on Tuesday and that 4,655 people had been saved, taking the total rescued to nearly 11,000 in just two days.

A coastguard spokesman said: ‘Obviously the good weather has played an important role in explaining the large number of recent arrivals.’

The number of pregnant women boarding migrant boats in Libya has risen significantly this year and it is not uncommon for them to go into labour as soon as they reach the safety of a rescue boat.

The latest surge in arrivals means at least 142,000 migrants have reached Italy since the start of the year. About 3,100 have died making the trip.

An estimated 154,000 came to Italy in 2015 and 2,892 died.

The majority of migrants come from Africa, including Nigeria, Eritrea, Guinea, Gambia, Sudan, Ivory Coast and Somalia.

Yesterday Greek police detained 214 Syrian refugees after they crossed a river that forms a border with Turkey.

It is the second time migrants have attempted to cross the Evros River in a week, and comes days after 107 were detained in the same area.