Migrant children play in the "Jungle," a migrant encampment in Calais, France, that is largely occupied by those hoping to illegally cross the English Channel and enter Britain by way of the Port of Dover in England. (Denis Charlet/AFP/Getty Images)

As the European Union continues to struggle to find a way to respond to the refugee crisis, children who live in unofficial refugee camps in northern France are being sexually exploited, trafficked and abused, according to a UNICEF report released this week.

The area nicknamed the "Calais Jungle" is home to an estimated 500 children who  have made the perilous journey alone. Often leaving their homes because of war, many find themselves trapped living in destitution, the most recent reflection of Europe's refugee system being weighed down by the enormous scale of the crisis.

Unaccompanied children are one of the most vulnerable groups reaching Europe's shores. Estimates suggest that almost 90,000 unaccompanied children made the journey into the European Union last year, a majority coming from war-torn countries such as Syria, Afghanistan and Iraq. Politicians and lawmakers throughout the E.U. have struggled to come to a solution, leaving many of the children stranded.

Calais is on the northern coast of France, close to Britain at one of the narrowest points of the English Channel. And it is to Britain that many migrants clustered in Calais are hoping to relocate. Going through the formal system, however, can take many months. According to the report, it can take up to 11 months for a child to be transferred to a country that has agreed to take him or her. Smugglers take advantage of this and have demanded payments of between $5,600 and $7,000 to speed up their journey.

The report found that unaccompanied children live in Calais for five months on average. During this time, many reported being sexually exploited in exchange for securing a spot in the camps.

Various factors have led to unaccompanied children's falling through the cracks. The slow process of turning political policies into reality is one factor. In March,  Labour and Conservative members of the British Parliament visited the camps in France and acknowledged the need to help the hundreds of children they saw living in abhorrent conditions. An arrangement was made to relocate 3,000 unaccompanied migrant children to Britain. It is unclear how many have been relocated so far. Citizens UK, a charity organization based in Britain, told the Guardian newspaper that it estimates that it could take one year for 150 children in Calais to be reunited with their families.

Lack of cooperation and failure by E.U. member states to follow through have also played a role in the crisis. At a summit in September, E.U. ministers approved a plan to relocate 160,000 migrants among E.U. member states. However, many states have fallen short under the agreement. "Just 17 member states have so far made 6,642 places available, about 4% of the promised total," the Guardian's Jon Henley wrote after examining official statistics.

Many recent arrivals also have had a difficult time understanding the asylum application process. Often, access to the Internet is required, which can be difficult to find. Other arrivals want to avoid applying for asylum until they reach their desired country.

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