About 340 migrants have been rescued and nine bodies have been pulled from the sea after a boat capsized in the Mediterranean Sea, Greek officials say.
Others are thought to be missing from the boat which was found in international waters, 75 nautical miles (140km) south of Greece’s Crete island.
Ships, helicopters and planes are engaged in the rescue operation.
In a separate incident, “more than 100 bodies” were recovered off the coast of Libya, the AP news agency said.
Officials have said they believe the vessel that capsized off the coast of Crete “left from Africa” though it is still not clear from where.
The local head of the International Organisation for Migration Daniel Esdras told the BBC that it was a 25-metre (82ft) boat that can typically carry at least 700 people.
“With the number you can never be sure because most of the times the minors are not even counted when the captain is counting the passengers. So, God knows how many people are really on the ship. We believe around 700,” he said.
More than 200 of the survivors were rescued by a Norwegian tanker ship. The Clipper Hebe has a crew of 21, and is now on its way to Italy. The CEO of the company that owns the ship, Edvin Andreason, told the BBC the Italian coastguard had not yet instructed the captain where to take the migrants.
A British container vessel, Julie C, later became involved in the rescue. It is carrying 17 rescued migrants who will later be transferred to an Egyptian patrol vessel.
Military hospitals in the north and west of Egypt have been put on standby for the migrants’ arrival.
Meanwhile, the number of dead from the boat that sank off Libya’s coastline has reached 107, Libyan Red Crescent spokesman Mohammed al-Mosrati said, quoted by AP.
They included 40 women and five children and are thought to have died in the past 48 hours, Mr al-Mosrati said.
They were washed up on a beach near the city of Zuwara, from which many unseaworthy boats are believed to have set out for Italy packed with migrants.
The UN said this week that more than 2,500 people had died in 2016 trying to make the journey towards Western Europe.
A recent improvement in weather conditions has led to an upsurge in the numbers of boats crossing the Mediterranean.
arrivals by sea in 2016, up to 1 June
376 died on Turkey-Greece route
52,871 persons of concern in Greece
856,723 arrivals in 2015
This marks the second time this week that migrants have had to be rescued in waters off the Greek coast. Up until now few migrants have landed on Crete, which lies north of Libya and Egypt.
Friday’s incident is likely to deepen concerns about a new smuggling route, one that could bring more tragedies at sea, following the closure of the Balkan route from Greece to Turkey in March.
Until the border closure, hundreds of thousands of migrants – many of them refugees from the Syrian civil war – streamed north through Greece, heading for Germany via the Balkans.
But border controls have since been tightened, leaving many asylum seekers stranded in Greece.
The EU has also struck a deal with Turkey to stem the flow of people risking their lives on flimsy boats crossing to Greece’s Aegean islands.
In the past week the focus has switched to the central Mediterranean, because of a surge in the numbers of migrants making the long, perilous voyage from Libya to Lampedusa and Sicily. Italy and its EU partners are struggling to shut down the route.