The EU is grappling with a spike in children trafficked for sex and other forms of slavery, according to experts.

"We have children being sold, we have women who are trafficked because they are pregnant in order for someone to buy their baby and sell it to the illegal market," Myria Vassiliadou, the European anti-trafficking coordinator, told reporters in Brussels on Thursday (19 May).

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Some children are forced to beg, others sold to criminal gangs (Photo: Council of Europe)

A small child is worth anywhere between €4,000 to €8,000 but in some cases up to €40,000.

Many are forced into sexual abuse, begging or delinquency with some taken away from impoverished families by criminal gangs as a form of debt relief.

Denmark, Lithuania, Sweden, and Slovakia have all reported an increase in children forced into committing crimes.

Around 2,375 children were registered as victims of human trafficking in the EU in 2013 to 2014 but the figures are likely much higher. The overall number, including adults, is 15,846.

Around two-thirds of all the registered victims are EU citizens. Most come from Bulgaria, Hungary, the Netherlands, Poland, and Romania. Others are brought in from Albania, China, Morocco, Nigeria, and Vietnam.

"Some people say it is the tip of the iceberg," noted Vassiliadou.

Fears are also mounting that children arriving in the EU seeking asylum may end up being trafficked. The EU commission cites research that suggests around 60 percent of all unaccompanied minors have gone missing from member state reception centres.

The EU police agency Europol earlier this year estimated at least 10,000 migrant children are missing.

Removal of organs

While almost all those who fall prey to traffickers are exploited for sex, around 12 percent end up in an "other" category that includes organ removal, forced begging, and turning others into drug mules.

"We are talking about people who have been forced into having their organs removed and either not being paid at the end or end up dying and people buying organs in the black market without asking where these organs come from," she said.

The grim figures are part of much larger report on victims of human trafficking in the EU published on Thursday by the EU commission .

The annex of the report notes organ removals in Bulgaria and Sweden, organ trafficking in Italy, and organ harvesting in the UK.

Vassiliadou was unable to provide more details on the organ crimes when pressed but said figures are likely to be disclosed in a separate report from the EU's statistical office Eurostat before the end of next year.

"We are not talking about organ trade here, we are talking about the trafficking of people for the purpose of organ removal," she noted.

Member states in 2011 transposed an EU directive to fight human trafficking. But only around half consider it a crime, depending on the severity of the case like labour exploitation, should someone knowingly exploit the services of a victim.

"So you can use the services of the victim of trafficking and you are not criminalised," said Vassiliadou.

An article (18.4) in the directive only instructs member states to consider criminalising people who exploit such services.

Criminal networks are reaping billions in profits. Few are prosecuted and sent to prison. Around 4,000 were prosecuted in 2013 and 2014 with just over 3,100 convicted of human trafficking.