A small boat carrying migrants hoping to get to Greece sank near the eastern island of Lesvos early on Saturday, drowning 20 people, Greek police said.
The boat had set off from the nearby Turkish coast carrying 27 migrants and its captain. It capsized about one mile (1.6 km off the coast of Lesvos due to strong winds, according to a survivor, police said.
"The survivor told coast guard authorities all the immigrants were from Iraq and had paid about 2,000 dollars per head to be transported to the island," a police official said.
The Greek coast guard found 20 bodies in the sea and was searching for any remaining survivors, the official said.
Thousands of illegal immigrants cross the country's porous sea and land borders every year, the vast majority via Turkey.
With Greece in its fifth year of a deep recession and hit by rising crime levels, illegal immigration became a major issue in the national elections earlier this year.