A Greek coast guard patrol boat collided with a dinghy carrying migrants to the island of Kos from Turkey on Wednesday, leaving a child dead and another person missing, authorities said.
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."