Officials on Kos said that 31 people were rescued following the collision, in an effort assisted by private boats and the European Union border protection agency Frontex. The circumstances of the collision weren't immediately clear.
The crash occurred before sunrise Wednesday in the heavily patrolled waters of the east Aegean Sea. "The search effort is focused on locating a missing 26-year-old Syrian man," coast guard spokesman Nikos Lagadianos said.
"The collision happened in total darkness ... they are trying to make the crossing undetected and the dinghies are usually overloaded with people. It is sometimes very difficult to detect those boats even for vessels equipped with radar."
Greek islands have seen a surge in recent months of refugees and migrants traveling in boats to the Greek islands to try and eventually reach EU countries. The government has intensified an effort to expand a network of refugee camps and hotel residence programs on the Greek mainland in an effort to ease severe overcrowding at facilities on the islands.
But on Wednesday protesting residents outside the northern city of Thessaloniki set up roadblocks to try and prevent migrants from settling in the area. A dozen buses transporting migrants were moved to a different location after a standoff between the protesters and police that lasted several hours. No arrests were reported.
A protest organizer, Theodoros Iordanides, argued that the distribution had been organized unfairly. "We were up all night, at three or four locations," he told The Associated Press. "Last year, 1,100 migrants settled here and no one complained even though it caused people in the tourism industry to lose income. But right now, our municipality has 2,500 migrants in total and the neighboring municipalities don't have any at all."
Derek Gatopoulos reported from Athens.
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