Survivors from a fishing vessel that sank off the coast of Greece said that some 100 children may have been aboard as Greek rescuers on Friday scanned the Ionian Sea by air and boat for survivors.
Hope faded of finding more people alive two days after a fishing boat overloaded with migrants capsized and sank, killing at least 78 people, off the Peloponnese. Some 104 people had been found alive.
The exact number of people aboard the boat is unknown, with one survivor telling hospital doctors in Kalamata he had seen 100 children in the boat's hold, broadcaster ERT reported.
"Hopes of finding survivors are fading each minute after this tragic sinking, but the search must continue," Stella Nanou, a spokeswoman for the UN refugee agency UNHCR, told AFP.
"According to broadcast images and accounts of some of the survivors, hundreds of people were aboard," she said.
The Greek coast guard said that rescuers scoured the sea through the night.
A helicopter, a frigate and three boats were scanning the waters on Friday, a coastguard spokeswoman told AFP.
Police on Thursday arrested nine Egyptians on suspicion of people smuggling – one of them the captain of the boat carrying the migrants.
They were detained at the port of Kalamata, where the survivors are being cared for, said Greek news agency ANA.
The survivors, mainly from Syria, Egypt and Pakistan, were being housed in a Kalamata warehouse.
Greece, Italy and Spain are among the main landing points for tens of thousands of people who seek to reach Europe as they flee conflict and poverty in the Middle East, Asia and Africa.