At least eight migrants have drowned after their boat crashed into rocks off the island of Lesbos, officials said.
The small vessel was carrying 19 illegal Afghan migrants from the nearby coast of Turkey.
Four women and four children drowned. A fifth child was reported missing, presumed dead, the coast guard said.
The survivors include one woman, one child and eight men. One of the group, a Turkish national, has been arrested on suspicion of people trafficking.
Strong winds were blowing in the area and by the time a Greek rescue helicopter and coast guard patrol boats reached the scene, eight people had drowned, authorities said.
Lesbos is one of the main points of arrival for illegal immigrants and asylum seekers who risk their lives in the hope of a better life in the European Union.
Smuggling gangs charge asylum seekers thousands of dollars to make the journey in unseaworthy vessels to Greek islands nestling close to Turkey's Aegean coast.
About 14,000 migrants arrived in Greece by boat in the first half of 2009, according to EU border agency Frontex.
The EU has pressed Turkey to take more action to control the flow of illegal immigrants, dozens of whom die in the crossing.