BUDAPEST (Reuters) - Hungary has ignored complaints about its practice of escorting undocumented immigrants back across the border to Serbia without due process, a watchdog group said on Tuesday after it raised the alarm about the ongoing human rights violations. Hungary’s nationalist government has long taken a tough stance on migrants and asylum seekers entering the European Union, an issue that has contributed to a sharp souring of relations with some EU partners. The European Court of Justice ruled in December that Hungary had broken EU laws on protecting migrants by denying them asylum and forcibly deporting them. Hungary is an EU member but Serbia is not. Since then, police data show Hungary has “escorted back” 2,346 undocumented immigrants, while it detained and started proceedings against only 120 people - meaning its primary method remained swift expulsion. The Hungarian Helsinki Committee, a legal advocacy group, urged Hungary’s police chief to end the practice and asked the EU’s border guard agency Frontex to cease cooperation with Budapest. “Neither the government nor Frontex replied to our letters,” Helsinki lawyer Andras Lederer told Reuters. A government spokesman said the EU ruling was “devoid of purpose as the circumstances at issue in the present proceedings no longer exist. Transit zones have been closed. However, strict border control is maintained.” Hungary closed the so-called transit zones last year. The zones had comprised shipping containers for lodging and were surrounded by heavily guarded barbed wire perimeters. Asked about the push-back practice, the government spokesman declined to comment, but added: “We will continue to protect the borders of Hungary and Europe, and will do everything we can to prevent the formation of international migrant corridors.” EU AGENCY “TURNED BLIND EYE” Frontex is “currently assessing the impact of the (EU court) ruling on our operational activities in Hungary,” Frontex spokesman Chris Borowski told Reuters, without elaborating. The Helsinki Committee’s request to Frontex to sever ties with Hungary was based on an earlier commitment by the agency to part ways with member states that breached human rights norms. In a separate report on the Frontex record in Hungary, the Helsinki Committee said “the Agency turned a blind eye towards well-documented systemic human rights violations at Hungary’s Schengen borders for more than four years”. Frontex did not immediately respond to questions seeking comment on that.