ATHENS — At least two people drowned when an overloaded boat carrying nearly 30 migrants sank off Greece’s eastern Aegean Sea island of Kos Wednesday, authorities said.

Greece’s coast guard said 24 people were rescued from the scene of the sinking, and a man and a woman were found dead. A coast guard statement added that according to survivors’ accounts, the boat had been carrying 27 people, which would leave one person missing.

The statement said several vessels and two aircraft were searching for other potential survivors.

It said the migrants’ plastic boat was detected by a thermal camera as it approached Kos, and a patrol vessel dispatched to investigate found an “overloaded polyester speedboat in dire straits, letting in water, which then capsized.”

The nationalities of the migrants were not immediately known.

The boat sank off Kos’ eastern coast, and is believed to have set off from the nearby Turkish coast. Thousands of migrants — mostly from the Middle East and Africa — try to reach the eastern Greek islands from Turkey every year, seeking a better life in the European Union.