Thousands of migrants have crossed the Mediterranean in the past few days, with European authorities warning that thousands more are waiting in Libya to make the journey. Find the key numbers

Thousands of people have illegally crossed the Mediterranean in the past few days, as good weather conditions encouraged would-be migrants to attempt the treacherous sea crossing. Rome says more than 50,000 migrants have landed in Italy by sea so far this year.

Harriet Sherwood writes today:



Up to 600,000 people are estimated to be waiting in Libya for an opportunity to make the treacherous sea crossing, prompting warnings by European authorities of an impending humanitarian crisis.

This is far from new, though – in October last year, around 500 migrants were en route to Italy when disaster struck and the ship they were on sank. Over 275 Eritrean migrants drowned, making it one of the highest verified death tolls of migrant ship disasters in the Mediterranean.

We reported earlier this month that officials had warned that hundreds of thousands of people would be preparing to make treacherous crossings on unseaworthy vessels from the north African coast to Greece and Italy as this summer's "boat season" gets under way.



Here are five things that explain a little bit more about the migration situation across the Mediterranean sea.



Who is travelling to Italy?

The top three nationalities of the top illegal border crossings into Italy and Malta, according to the European Union border coordination agency Frontex, are Eritrean, Syrian, and Somalian. Between 2012 and 2013, the total number of illegal border crossings (including all countries) into Italy and Malta increased by 388%.

Why did the numbers increase so much?

For the first half of 2013, Syria was the country with the largest number of displaced people, with 1.3m people seeking refuge in the surrounding countries, according to a mid-year report by the UN High Commissioner for Refugees (UNHCR). In that same period, Syrians accounted for eight out of 10 refugees.

The war in Afghanistan has also seemingly continued to affect migration and refugee numbers – just over 2.5m Afghans fled their home country in mid-2013. Refugees from Afghanistan, Syria, Somalia, Sudan and the Democratic Republic of Congo accounted for more than half (60%) of all refugees under UNCHR's responsibility



Major source countries of refugees Photograph: /UNHCR

So Italy has the most refugees from these countries?

Actually, Europe is not the main recipient of refugees from the Middle East and Africa. Refugees tend to migrate to countries that are nearby, in the hope that they are just far enough away to be out of harm’s way.

Europe is too far away to reach and too much of a risk. In fact, Pakistan took in the most refugees both this year and last, according to the UNHCR.

Major refugee hosting countries Photograph: /UNHCR

Why is Italy such a popular destination?

Greece was long thought of as the easiest way for potential refugees get into the EU, as its borders were very porous – the government could not afford to patrol the borders between Greece and Turkey.

But in late 2012, the Greek government erected a four-metre, six-mile barbed wire fence along the Greek-Turkish land border that would keep out potential asylum seekers. Since then, the flow of refugee seekers has moved from land to sea, to different Greek islands in the Aegean, and eventually Italy and Malta.

Plans to seal the Turkey-Bulgaria border will likely have a similar impact on the behaviour of desperate migrants fleeing from war and famine.



What’s being done about it?

Few would argue that those seeking refuge should be forced to stay in their home countries when war and famine strike, but Italy and Malta have both complained that they don’t have the resources to cope with the migration, and that Europe is not doing enough to help them.



Michele Cercone, the spokesman for the European Union Home Affairs Commissioner Cecilia Malmström, said that there would be full support for both Italy and Malta from the commission “by any means possible".



But he also pointed out that Italy had received an extra €30m since the two tragedies in October to help them cope with the numbers.

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