A rescue operation by the Greek coast guard was under way on Sunday after a Lithuanian helicopter from the European border patrol agency Frontex spotted several people in the waters off the coast of Lesbos, officials said.

Two coastguard vessels managed to rescue 20 people, but the survivors say there were a total of 46 people on board the inflatable dinghy, with which they were trying to make the crossing from Turkey to Europe.

The nationalities of the migrants was not immediately known.

Journey short, but perilous

Hundreds of thousands of asylum seekers, many from conflict-ridden Syria, have arrived in Greece from the nearby Turkish coast so far this year, but many refugees have also lost their lives trying to cross the Aegean Sea in search of a better life.

Rescues and sinkings have become almost commonplace as the often flimsy vessels attempt to navigate the frequently choppy sears surrounding Greece's eastern islands.

Thirty-four refugees, including 15 babies and children, died a week ago when their boat capsized off the small Greek island of Farmakonisi, while 13 others were feared lost overboard on Saturday after their boat also sank off Lesbos, which is a favored entry point to Europe for refugees hoping to head further north to countries such as Germany and Sweden.

A number of migrants have attempted to avoid the sea crossing by turning to Turkey's land borders with Greece and Bulgaria, but have been stopped from reaching the frontiers by Turkish authorities.

tj/rc (Reuters, AP, AFP)