An air and sea rescue operation was underway on Wednesday after around 50 people went missing when a migrant boat sank in the Aegean Sea, the Greek coastguard said.
The vessel foundered at dawn off the islands of Karpathos and Rhodes after setting sail on Tuesday from Antalya, southern Turkey, heading for Italy.
"According to the statements of 29 rescued people, there were 80 people on the boat, so up to 50 people are missing," a coastguard press office official told AFP.
But state television channel ERT said the number of people on board had been between 30 and 60.
Coastguard spokesman Nikos Kokalas told the channel: "It's not possible that the boat could have been transferring 80 migrants. We are talking about a lower number."
The rescue effort, ordered by Merchant Shipping Minister Yannis Plakiotakis, according to a coastguard statement, included four vessels already sailing in the southern Aegean, two coastguard patrol boats and a Greek air force helicopter.
Strong winds of up to 50 kmph were hampering the operation, Mr. Kokalas told Skai radio.
"Many of those shipwrecked were not wearing life-jackets," Mr. Kokalas said.
A video posted by the coastguard showed an army helicopter rescuing two survivors from the sea and transferring them to Karpathos.
Another 27 people were transferred to land aboard a tanker that joined the search off the island of Kos, said the coastguard.