The man’s story echoes complaints from human-rights groups that Greek authorities often expel asylum seekers indiscriminately and violently.
For years, Greek officials have denied complaints from human rights groups that the country’s border agents have brutalized migrants and forcibly pushed them back into Turkey. They have dismissed the allegations as fake news or Turkish propaganda.
Now a single case may force a reckoning.
A European Union interpreter says that in September, Greek border guards mistook him for an asylum seeker, assaulted him and then forced him across the border into Turkey alongside dozens of migrants.
His allegation is particularly problematic for Greek officials because he is a legal European Union resident employed by the E.U. border agency, Frontex. And he has turned over evidence to the agency to support his claims of abuse, according to European officials dealing with his case.
The European Union, which has mostly looked the other way on abuses of migrants, is now being forced to confront the problem.
Surfacing in the wake of an acute border crisis with Belarus over migrants, the case has commanded the attention of senior European leaders for weeks. Ylva Johansson, the European commissioner for migration, said she called the interpreter on Friday to discuss his accusations.
“After direct, in-depth discussion with the person on Nov. 25, I was extremely concerned by his account,” Ms. Johansson said. “In addition to his personal story, his assertion that this was not an isolated case is a serious issue,” she added, saying he told her he had witnessed at least 100 migrants who were pushed over the border and sometimes roughed up
However, a Greek government ministry statement cast doubt on his account, saying initial inquiries suggested “the facts are not as presented.”
The interpreter told The New York Times that he had filed a complaint with Frontex, and European officials confirmed this. They said the complaint was being treated as credible because of the man’s position and the documentation he provided, including audio and video recordings.
The man asked not to be identified out of concern for his safety and his livelihood. Two European officials, speaking on condition of anonymity because they were not authorized to discuss the case with reporters, confirmed his identity.
He said that he and many of the migrants he was detained with were beaten and stripped, and that the police seized their phones, money and documents. His attempts to tell the police who he was were met with laughter and beatings, he said. He said he was taken to a remote warehouse where he was kept with at least 100 others, including women and children. They were then put on dinghies and pushed across the Evros River into Turkish territory.
His accusations were similar to those from human-rights groups, along with mounting evidence gathered by migrants and reporters, all claiming that Greek authorities routinely round up and expel migrants without permitting them to complete asylum requests — often in an indiscriminate and violent way. Greek authorities have also been accused of pushing back migrants in flimsy dinghies in the Aegean Sea, sometimes disabling the engines and leaving the migrants to drift back into Turkish waters. Greece has denied the accusations.
The man’s story came to light at a critical moment in Europe’s reckoning with its practices in dealing with migrants, which have drawn renewed scrutiny after a standoff at the Belarus-Poland border that left 12 migrants dead. In a bid to put pressure on the European Union over a geopolitical standoff, Belarus lured migrants into its territory, left them in a frigid forest and encouraged them to cross into E.U. countries, including Poland. Polish authorities repelled them, sometimes violently.
That crisis, together with a similar standoff between Greece and Turkey last year with asylum seekers caught in the middle, has laid bare a growing gulf between European laws and norms in treating asylum seekers, and the reality on the ground.
Public opinion toward immigration soured after the Syrian war brought more than one million refugees to Europe in 2015-16. Still, in much of the European Union, politicians and citizens oppose inhumane and illegal practices such as rounding up migrants and expelling them without due process.
But governments at Europe’s frontiers, such as Greece, view migration laws and procedures as out of date and out of step with the current climate, contending that they were designed before the mass population displacements seen in recent years.
Prime Minister Kyriakos Mitsotakis of Greece, in remarks this month, rejected accusations of abuses against migrants by the Greek authorities. He called his migration policy “tough, but fair.”
Ms. Johansson said she had spoken on Monday with the Greek minister for citizen protection, Takis Theodorikakos, and he promised to investigate the interpreter’s claims.
“The independent National Transparency Authority will conduct an investigation and will be open about its findings as always, but preliminary inquiries in this case appear to suggest the facts are not as presented,” the ministry’s media office said in a statement.
Sophie in ‘t Veld, a Dutch member of the European Parliament, said the interpreter’s allegations were part of a pattern of growing E.U. brutality toward migrants and asylum seekers.
“With tens of thousands of victims who drowned in the Mediterranean, thousands languishing in what has been described as concentration camps in Libya, the misery in the camps on the Greek islands for so many years, people drowning in the Channel or freezing to death on the border between Belarus and the E.U., the European Commission cannot claim anymore that these are incidents, accidents, exceptions,” she said.
“It is not a policy failure,” she added. “It is policy.”
Greece, one of the main gateways into the European Union for migrants, has long maintained that it is being asked to rescue, process and host too many people arriving from Turkey, a hostile neighbor that often encourages asylum seekers to go to Greece to provoke the government there and to press its demands with the European Union.
Under Greek and E.U. laws, the Greek authorities are required to assess asylum requests for all who seek protection, to house asylum seekers in humane conditions and, if they are rejected, to repatriate them safely.
Efforts to more fairly distribute asylum seekers across the European Union have stalled, as many member countries prefer to send funding to Greece and other frontier nations to host asylum seekers, and keep them away from their territories.
Frontex and the European Asylum Support Office pay and deploy hundreds of employees to ensure that the bloc’s external borders are guarded while human rights laws are upheld.
The interpreter, who is originally from Afghanistan, has lived for years as a legal resident in Italy. He was employed by Frontex as a member of an E.U.-funded team of experts deployed to help the border guards communicate with asylum seekers.
He had been working in the border region of Evros alongside Greek and E.U. guards, and was on his way to Thessaloniki, Greece’s second-largest city, for a break when the police pulled him and a number of migrants off a bus, he said.
After they were beaten, detained and forced into Turkey, the interpreter said, he managed to reach Istanbul, where he received consular assistance from the Italian authorities, and was eventually repatriated to Italy on Sept. 18.
The Italian foreign ministry did not immediately respond to requests for comment.
A Frontex spokesman said the agency was investigating the report and could not comment further as long as the investigation continues.