Lampedusa on Sunday.

The IOM believes the number of migrants dying in Mediterranean Sea crossings could hit 30,000 this year if the current rate continues.

Federico Soda, IOM's Italy director, said the Italian maritime forces were doing "incredible work" trying to rescue as many people as possible, but that the rising number of deaths was "unacceptable".

"Search and rescue efforts must be more comprehensive and supported by the European Union and its member states. This is a humanitarian emergency that involves us all and responses to it must be more holistic."

Perilous journeys

By far the largest number of migrant deaths internationally have taken place in the Mediterranean, according to the IOM. The figures are striking. Not including Sunday's sinking, nearly eight out of every 10 deaths have taken place there this year.

By comparison, the second highest number of migrants died in the Horn of Africa where fewer than one in 10 deaths occurred. Of those migrants who die in the Mediterranean, the vast majority of them began their journey in Sub-Saharan Africa.

Most dangerous routes

Within the Mediterranean, the Central migration route from North Africa to Italy and Malta is the deadliest.

So far this year, 910 people have been killed as a result of attempting the journey. The 800 potential victims of Sunday's sinking are also likely to join their number.

A much smaller number of migrants died travelling along the Mediterranean's other routes - to its east and west and towards Apulia and Calabria, Italy.

Last year, a total of 3,279 migrants were killed as a result of their journey across the sea to Europe. Again, by far the majority died along the Central Mediterranean route.

Death rate

Image copyrightGetty Images

Some 912 out of 954 of this year's deaths have been on routes towards Italy, as of 17 April.

The IOM estimates that 21,191 migrants have reached the Italian coasts alive during the same period.

This makes the rate of death en route to Italy so far this year 4.13 per 100 people.

By comparison, some 26,644 migrants had made it alive to Italy by 30 April last year - an increase of 5,000 more than this year - according to data provided by the Italian Ministry of Interior.

Who are the victims?

Image copyrightGetty Images

Looking back to 2014 as a whole, the African nations with the most migrants reaching Italy were Eritrea, Mali and Nigeria. The numbers of men braving the journey vastly outnumbered the women.