Authorities on the Greek island of Lesbos search Thursday for 38 people believed still missing after the sinking of a wooden boat carrying migrants. Earlier, 242 people were rescued and three bodies were recovered.

At first light Thursday, a helicopter from the European border protection agency Frontex joined the search by Greek coast guard vessels off the northern coast of the island.

At least 11 people — mostly children — died in five separate incidents in the eastern Aegean Sea on Wednesday as thousands of people continue to head to the Greek islands from Turkey in frail boats and stormy weather.

Lesbos has borne the brunt of the refugee crisis in Greece, with more than 300,000 reaching the island this year — and the number of daily arrivals recently peaking at 7,500.

In a dramatic scene late Wednesday, dozens of paramedics and volunteers helped in the effort to assist the survivors, wrapping them in foil blankets and prioritizing ambulance transport.

Eighteen children were hospitalized, three in serious condition, local authorities said.