A major rescue operation is underway and hundreds are feared drowned after a small fishing boat carrying up to 700 migrants sank off the coast of Libya.
The incident was reported by Irish navy officials, who told the Associated Press a number of ships and Italian military helicopters were being deployed to try and save lives.
Some 150 migrants were spotted in the water, Captain Donal Gallagher said.
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An Italian coastguard spokesman said the overcrowded boat went over just as ships were approaching to rescue its passengers, but was unable to provide details on the numbers involved.
Captain Gallagher estimated around 600 on board in total, while the SkyNews24 TV channel reported it as around 700. Stranded migrants spend night on rocks
More than 2,000 migrants have died already this year as the Mediterranean crisis worsens, compared with 3,279 deaths during the whole of last year, according to the International Organisation for Migration. It makes the sea the most deadly border area in the world for migrants.
The Irish naval vessel Le Niamh was one of several ships requested by the Italian coastguard to speed to the rescue, Capt Gallagher said.
Also involved in the rescue were an Italian vessel and a boat operated by Doctors Without Borders (MSF).
The distressed vessel was reported to be about 75 miles north west of Tripoli, Libya's capital.
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