Eight refugees were reported missing on Thursday after a wooden boat capsized off the coast of Lesvos island in the Aegean Sea, the Greek coast Ggard said.
The wooden boat was carrying 39 people from Turkey's coast to Greece. It capsized after colliding with a Greek coast guard vessel, Xinhua news agency reported.
Thirty-one people were rescued during an ongoing search operation, according to Greek authorities.
The coast guard said the collision happened when the Turkish smuggler tried to escape and resorted to dangerous manoeuvres. It was still unclear whether he was among the survivors or the missing.
According to the latest data, Greek authorities have rescued 141,919 undocumented migrants and refugees on the Mediterranean Sea in 795 incidents this year alone. More than 3,000 people have perished.
Meanwhile, about 400,000 people have illegally entered Greece since the beginning of the year.