At least 45 people including 17 children have drowned in the Aegean Sea as two migrant boats sunk off Greek islands.

The Greek coastguard and other boats saved more than 70 people from the sunken vessels, and a search-and-rescue operation is under way for others feared trapped in the wreckage..

One wooden boat carrying 49 people foundered off the small Greek islet of Farmakonissi. Forty people made it to shore, while authorities rescued one girl and recovered eight bodies from the sea - six children and two women, the coastguard said.

A few hours later, a wooden boat carrying an undetermined number of people sank off the islet of Kalolimnos, south of Farmakonissi. The coastguard rescued 22 men and four women, and recovered 34 bodies - 16 women, seven men and 11 children.

Turkey's state-run Anadolu news agency said the Turkish coastguard rescued six survivors from the area of the two accidents and found another three bodies.

One survivor told APTV that the vessel's engine failed five hours after they departed from Izmir in Turkey. Speaking at a reception centre on the island of Kalymnos, he said about 80 people on board had paid 2,500 US dollars (£1,740) each for a berth, with half that sum for children.

The new drownings follow hundreds over the past year as Europe faces its worst immigration crisis since the end of the Second World War. More than a million people seeking asylum entered the continent last year - most through Greece, coming across the sea in small smugglers' boats from Turkey.

The European Union is deeply divided on addressing the influx, with several countries blocking or restricting migrants from entering and resisting plans to share the burden of refugees. In the meantime, Germany - where most immigrants are heading - has welcomed those it considers refugees.

EU foreign policy chief Federica Mogherini said on Friday that the 28-nation bloc faces big economic risks if member countries start putting up walls between each other that restrict borderless travel.