Hungary forced 11 Afghan nationals to cross into Serbia after rejecting their asylum requests, a rights advocate said on Wednesday, and deported a 12th convicted of people smuggling back to Kabul.

The deportation of a further five Afghans, all members of the same family, was temporarily suspended following an appeal to the European Court of Human Rights by the Hungarian Helsinki Committee, a human rights group.

The United Nations refugee agency (UNHCR) said Hungary’s action to force the two families to leave the country was a flagrant violation of international and EU law.

Under Hungarian law, the claims of asylum-seekers arriving from a country that Hungary deems safe are rejected, the agency said in a statement, adding that the case highlighted deep concerns over that practice.

The Hungarian Immigration and Asylum Office (IAO) said the measures were part of a joint operation with European border and coast guard agency Frontex, in which 39 people were flown to Afghanistan altogether.

The Helsinki Committee said the Hungarian operation targeted three Afghan families. Two families, including a pregnant woman, were moved to Serbia overnight.

These people were put in an impossible situation, said Andras Lederer, a Helsinki information and advocacy officer. ... Either (to) return to Kabul or cross over into Serbia in the middle of nowhere late at night.

The IAO said 11 people choose to go to Serbia. The Serbian authorities had given the families accommodation in a reception center, the UNHCR said.

An interior ministry media officer said the single Afghan deportee had been convicted of people smuggling.

Lederer said the family of five was being held at a border transit zone while their case was pending. The European Court of Human Rights did not immediately respond to emailed questions for comment.

The IAO said before arriving to Hungary, the asylum-seekers had passed through several countries, including an EU member state, where they had access to medical and other assistance.

Hungarian Prime Minister Viktor Orban leads a nationalist government with a strongly anti-immigrant platform, which is a key plank of the ruling Fidesz party’s campaign for the European Parliament elections on May 23-26.

The UNHCR has advised Frontex to refrain from supporting Hungary in the enforcement of return decisions which are not in line with international and EU law, the refugee agency said.