New migrant tragedy off Greece as Athens dismisses criticism

At least 28 people drowned in another migrant tragedy off Greece on Sunday, as Athens angrily defended its handling of the mounting refugee crisis in Europe.

Among those who lost their lives was a baby, the Athens News Agency reported, when the stricken boat carrying 112 people sank off off the southern Aegean island of Farmakonisi.

A search and rescue effort is under way in the area, the coastguard said, giving an updated death toll of 28 dead.

Another 68 people were plucked alive from the sea while a further 29 managed to swim to safety on a beach on the island, it said.

The coastguard was also still searching for four children missing after another boat capsized on Saturday off Samos, a Greek island just off the Turkish coast.

The latest tragedies follow the death of a Syrian toddler whose lifeless body was photographed washed up on a Turkish beach, becoming a heart-wrenching symbol of the plight of refugees fleeing war.

The International Organisation for Migration has said more than 430,000 migrants and refugees had crossed the Mediterranean to Europe so far in 2015, with 2,748 dying or going missing en route.

Interim Prime Minister Vassiliki Thanou on Sunday branded criticism of Greece, which has been on the frontline of the surge of migrants trying to reach Europe, as "unacceptable".

"Greece is strictly applying European and international treaties without ignoring the humanity of the situation," she said on a visit to Lesbos, an island which has been struggling with the massive influx.

German Chancellor Angela Merkel on Saturday called on Athens, already grappling with a deep economic crisis, to make more effort to protect the EU's external borders.

"We have a second external border, that's between Greece and Turkey, where we need protection. And this protection is at the moment not being guaranteed," she said.

"Greece needs to take its responsibility... we will also speak with Turkey."