The number of asylum seekers returned to Italy from elsewhere in Europe under a controversial EU regulation has almost tripled in five years, amid concern over their treatment in Italy and Germany.

Under the terms of the Dublin regulation, member states can send people back to their country of arrival in the EU – usually Italy or Greece.

According to data from the Italian interior ministry, between January 2013 and November 2018, 24,000 people were returned to Italy from elsewhere in Europe. About 6,500 people were returned in 2018, compared with just under 2,500 in 2014, according to data from a database managed by the European Council on Refugees and Exiles. As it stands the number of people being returned to Italy could soon exceed those arriving across the Mediterranean from Libya.

Despite the increase, the numbers are a small fraction of the 188,000 requests for transfers to Italy made since 2013, said Matteo Villa, a research fellow from ISPI, an Italian migration thinktank. Requests have come mainly from four countries – Germany (35% of the total), Switzerland (21%), France (19%) and Austria (8%).

Aid agencies have reported incidents of brutality and violence towards people sent back to Italy. Late last year a report by the Danish and Swiss refugee councils found that vulnerable asylum seekers returned to Italy faced arbitrary access to accommodation, risk of destitution and substandard reception conditions.

A cat-and-mouse situation has played out between Italy and France at the Italian border town of Ventimiglia since 2011, with French police accused of illegally sending back thousands who have tried to cross the border, either by train or via a dangerous mountain path.

French border police have also been accused of detaining migrant children as young as 12 in cells without food or water, cutting the soles off their shoes and stealing sim cards from their mobile phones, before illegally sending them back to Italy.

Last week Italy’s La Repubblica alleged that asylum seekers in Germany who resisted deportation were sedated and put on chartered flights to Italy.

In February, the German government released figures that showed an almost tenfold increase since 2015 in measures to forcefully restrain returned asylum seekers.

In 2018 authorities resorted to “aids to physical violence”, such as handcuffs, in 1,231 cases, up from only 255 in 2015. The same month MPs from Germany’s Die Linke party called for a parliamentary inquiry into reports of police violence during collective deportation procedures, including the use of sedatives.

In response to the recent allegations the German government said the responsible authorities had not filed a report on the cited incidents. In principle, a spokesperson for the interior ministry said, it was illegal for police to administer medication unless there was a strong medical reason to do so. “Guaranteeing an unproblematic return,” the ministry said, was not sufficient grounds for a legal medical intervention.

If the allegations in La Repubblica are verified it would cast a disturbing light on the German authorities’ conduct, said Riccardo Noury, a spokesman for Amnesty International in Italy.

Noury also accused the Italian government of disengaging with efforts to reform the Dublin regulation, which critics say places an undue burden on countries like Italy simply because of their proximity to departure countries for migrants, such as Libya.

Matteo Salvini, Italy’s far-right interior minister, has attacked EU countries that refuse to take in people who arrived on the continent in Italy. However, not only did he abstain during a vote to amend the regulation, he did not participate in any of the 22 negotiation sessions on the subject in two years.

The reason for this absence is unclear, but modifying the law would ameliorate Italy’s situation and, from the perspective of Salvini’s League party, allow the country to take in fewer migrants.

“Italy’s interior minister has repeatedly attacked EU countries that refuse to take in migrants that disembarked onboard NGO rescue boats which ignored his veto to enter Italian waters,” said Fulvio Vassallo, professor of asylum law at the University of Palermo. “But if Salvini had participated to the negotiation sessions to change the Dublin regulation maybe Italy could have killed two birds with one stone: the obligatory re-placement of migrants for all EU states and a better relocation to the asylum seekers.”