The Greek coastguard early on Thursday rescued more than 40 undocumented migrants stranded on an Aegean Sea islet, though one of them later died in hospital, a spokeswoman said.
The 47 migrants -- who lacked identity papers but said they were from Syria, Afghanistan and Cameroon -- were found on an islet near the island of Chios.
"They were airlifted by rescue helicopter," the coastguard spokeswoman said.
"One of them was unconscious and later died in hospital but the rest are fine and will undergo routine health tests," she added.
Greece is a major entry point into the European Union for migrants and refugees fleeing war-torn or impoverished countries in Africa, the Middle East and the Indian subcontinent.
The influx has put additional strain on the recession-hit country's health services and prison facilities, forcing Greece to turn to the EU for help to patrol its extensive maritime frontiers.