Nearly 6,000 refugee children and minors were reported missing in Germany last year, according to latest figures from the country’s interior ministry.

The high number confirms that the plight of unaccompanied child refugees is rapidly becoming one of the most urgent issues of the on-going migrant crisis, as concerns grow that traffickers and criminals are exploiting the crisis to prey on vulnerable young people.

Europol – the EU’s law enforcement agency – has previously estimated that at least 10,000 refugee children went missing on the continent over the last year. “This does not mean that something happened to all of them,” a Europol spokesperson told reporters at the time. “A portion of the children could in fact be staying with relatives. But it does mean that these children are potentially at risk.”

According to the Local, an answer from the interior ministry to the German Parliament revealed that last year 5,835 unaccompanied teens and children were reported missing. Of those, 555 were younger than 14-years-old.

"The missing, unaccompanied, underage refugee children came mainly from Afghanistan, Syria, Eritrea, Morocco and Algeria," stated the Interior Ministry. But the ministry did not elaborate on a reason for why they were missing.

"This handling of the most vulnerable people looking for protection shows cold-heartedness with family reunification being severely curtailed," Luise Amtsberg, a Green Party politician in the German Parliament, told the Westdeutsche Allgemeine Zeitung.

Refugees break through Macedonia border fence in February Show all 15 1 /15 Refugees break through Macedonia border fence in February Refugees break through Macedonia border fence in February Stranded refugees try to bring down part of the border fence during a protest at the Greek-Macedonian border, near the Greek village of Idomeni Reuters Refugees break through Macedonia border fence in February Stranded refugees try to break a Greek police cordon in order to approach the border fence at the Greek-Macedonian border, near the Greek village of Idomeni Reuters Refugees break through Macedonia border fence in February Stranded refugees flee tear gas fire by the Macedonian police, after trying to bring down part of the border fence during a protest at the Greek-Macedonian border, near the Greek village of Idomeni Reuters Refugees break through Macedonia border fence in February Stranded refugees try to break a Greek police cordon in order to approach the border fence at the Greek-Macedonian border, near the Greek village of Idomeni Reuters Refugees break through Macedonia border fence in February Stranded refugees in the northern Greek village of Idomeni approach the Greek-Macedonian border as they try to enter Macedonia AP Refugees break through Macedonia border fence in February Macedonian riot police officers stand next to part of the border fence brought down by protesting stranded refugees and migrants during a protest at the Greek-Macedonian border, near the Greek village of Idomeni Reuters Refugees break through Macedonia border fence in February Stranded refugees try to bring down part of the border fence during a protest at the Greek-Macedonian border, near the Greek village of Idomeni Reuters Refugees break through Macedonia border fence in February Stranded refugees break an iron fence and throw stones from the Greek side of the border as Macedonian policemen push them back, near the southern Macedonian town of Gevgelija AP Refugees break through Macedonia border fence in February A girl cries as she flees clashes during a protest at the Greek-Macedonian border, near the Greek village of Idomeni Reuters Refugees break through Macedonia border fence in February Refugees try to broke an iron fence from the Greek side of the border as Macedonian police stand guard, near the northern Greek village of Idomeni AP Refugees break through Macedonia border fence in February Stranded refugees and migrants in the northern Greek village of Idomeni approach the Greek-Macedonian border as they try to enter Macedonia AP Refugees break through Macedonia border fence in February A man helps children to run away after Macedonian police fired tear gas at a group of refugees who tried to push their way into Macedonia AP Refugees break through Macedonia border fence in February A woman carries a child on the Greek side of the border as they run away after Macedonian police fired tear gas at a group of refugees who tried to push their way into Macedonia AP Refugees break through Macedonia border fence in February Refugees run away after Macedonian police fired tear gas AP Refugees break through Macedonia border fence in February A woman falls as refugees with their children run away after Macedonian police Getty Images

Eurpol’s chief of staff Brian Donald said to the Observer last month that 5,000 children had disappeared in Italy alone. He added: “It’s not unreasonable to say that we’re looking at 10,000-plus children. Not all of them will be criminally exploited; some might have been passed on to family members. We just don’t know where they are, what they’re doing or whom they are with.”

Mariyana Berket, of the Organisation for Security and Cooperation in Europe (OSCE), said to the newspaper: “Unaccompanied minors from regions of conflict are by far the most vulnerable population; those without parental care that have either been sent by their families to get into Europe first and then get the family over, or have fled with other family members.”