The 47-nation Council of Europe — the continent's main rights grouping — accused Hungary on Friday of mistreating migrant children aged from 14 to 18 at its border despite past prompts to uphold Europe's Convention against Trafficking in Human Beings.

Delegations that visited the zone in July and December last year found scores of unaccompanied migrant teenagers from countries including Afghanistan and Syria in confined container camps, surrounded by barbed wire and overseen by armed guards.

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Council of Europe experts sad in the report to be published Friday that asylum-seeking children were also at risk of being "asked for sexual favors" to be moved up the lists of migrants waiting to enter Hungary.

Hungarian law sidesteps convention

The report criticized Hungary for passing a law in March 2017 that overrode international child protection safeguards in cases of "crises" and classing them as adults who can be required to be held at border transit zones.

Instead of security personnel, the children needed trained professionals in a "climate of trust" who were also able to help with language translation, the Council of Europe said.

Article 1 of the UN Convention the Rights of the Child, of which Hungary has been a signatory since 1990, defines a child as "every human being below the age of 18."

Hungary: zone not closed

The Hungarian Interior Ministry rejected the criticism, saying the transit zones were not closed but open in the direction of Serbia.

"Every asylum-seeker can return at anytime to Serbia," the ministry said in a statement.

Hungary became a signatory to the anti-trafficking convention in 2008. It became applicable on its territory in 2013 – before Europe's 2015 political crisis over refugee arrivals along the so-called Balkan route.

In March 2017, a Helsinki Committee report concluded that Hungary was not maintaining an asylum procedure that took a child's best interests to be of paramount importance.