An enormous search operation is constant for "hundreds" of lacking migrants after a minimum of 78 drowned when a fishing boat sank off the coast of Greece.

Officials mentioned 104 survivors had been rescued after the vessel capsized about 50 miles from the southern coastal city of Pylos.

But charity Alarm Phone, which operates a community supporting rescue operations and obtained frantic calls from a few of these on board, mentioned as much as 750 folks might have been on the vessel.

Greek officers mentioned the boat received into difficulties when its engine stopped and it started veering back and forth. It then capsized and sunk at round 2am on Wednesday.

Shortly beforehand, Alarm Phone mentioned it spoke to somebody on board who mentioned: "The captain left on a small boat. Please, any solution."

They additionally pleaded for meals and water, and mentioned the vessel had stopped shifting, based on the charity.

The seek for survivors continued on Thursday morning and is anticipated to final till a minimum of Friday, Greek authorities mentioned.

Six coast guard vessels, a navy frigate, a navy transport airplane, an air drive helicopter, a number of personal vessels and a drone from the European Union border safety company, Frontex, are participating within the operation.

Officials mentioned it was unlikely the sunken boat can be recovered as a result of the realm of worldwide waters is without doubt one of the deepest within the Mediterranean.

Alarm Phone accused Greek and different European authorities of failing to launch a rescue operation earlier than the boat sunk, regardless of being "well aware of this overcrowded and unseaworthy vessel".

The Greek coast guard denied the declare and mentioned these on board "refused our assistance because they wanted to go to Italy".

Spokesperson Nikos Alexiou added that they nonetheless stayed close by "in case it needed our assistance which they had refused".

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Aerial footage launched by the Greek coast guard confirmed the 20 to 30 metre-long boat hours earlier than it sank.

Dozens of individuals on the higher and decrease decks had been seen wanting up, some with arms outstretched.

Witnesses mentioned many extra girls and kids had been under within the maintain, based on native stories.

Greek authorities, who initially mentioned 79 folks had died earlier than later revising the determine all the way down to 78, mentioned they might not affirm how many individuals had been on board.

The UN's International Organisation for Migration mentioned preliminary stories recommended there have been as much as 400 folks on the vessel.

The boat is believed to have set off from the Libyan port of Tobruk and was heading to Italy.

Greek authorities mentioned many of the migrants had been from Egypt, Syria and Pakistan.

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It comes as Libyan authorities launch a significant crackdown on migrants, with a number of thousand - together with Egyptians, Syrians, Sudanese and Pakistanis - detained.

Many Egyptians have been deported to their dwelling nation by means of a land crossing level.

The area is without doubt one of the most important routes into Europe for refugees from the Middle East, Asia and Africa.

The UN mentioned there have been greater than 20,000 deaths and disappearances within the Mediterranean since 2014, making it probably the most harmful migrant crossing on the earth.