At least seven migrants have died, including one boy, one girl and two women, after their boat sank off the Greek island of Lesbos, Greece's coastguard said on Thursday.
The boat was detected by a patrolling coastguard vessel in the early hours in the north of Lesbos.
So far 23 migrants have been rescued and a search and rescue operation was still ongoing, a coastguard official said. It was not immediately clear how many people may have been on the boat.
Greece, in the southeast corner of the European Union, has long been a favoured gateway to Europe for migrants and refugees from the Middle East, Africa and Asia. In 2015 nearly 1 million people landed on its islands.
Last year, about 54,000 migrants reached Greece, the second largest number in southern Europe behind Italy. The vast majority of them arrived by sea, according to data from the UN refugee agency UNHCR.
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