ATHENS – Greece’s assertions that refugees and migrants haven’t been pushed back in the Aegean and across land borders with Turkey were seemingly undercut when a European Union interpreter said he was caught up in an incident where they were.

The interpreter, whose name was not given, told The New York Times that Greek border guards assaulted him and then forced him across the border into Turkey alongside dozens of migrants although he works for the EU border agency Frontex.

As a legal EU resident working for a key agency in the bloc – itself accused of aiding Greece in pushbacks and the European Parliament demanding answers – his allegations have put Greece in a difficult spot.

Ylva Johansson, the European commissioner for migration, said she called the interpreter to discuss his accusations and told the newspaper that, “His assertion that this was not an isolated case is a serious issue.”

She said he told her he’d seen at least 100 migrants pushed back and sometimes also assaulted although a Greek government ministry statement dismissed it and said the initial inquiries suggest “the facts are not as presented,” the report added.

The interpreter told The New York Times that he had filed a complaint with Frontex, which EU officials confirmed, adding it was credible because of his position and that he provided audio and video recordings.

The newspaper was among major media who earlier reported on pushbacks denounced by human rights groups and activists, with Turkey making similar claims without mentioning it allowed human traffickers to keep sending them.

That violates the terms of an essentially-suspended 2016 swap deal with the EU while Greece said Turkish President Recep Tayyip Erdogan is using the threat of sending more to make the bloc meet his demands.

Under the deal, Turkey is supposed to contain some 4.4 million refugees and migrants who went there fleeing war, strife and economic hardship in their homelands.

Turkey was to get six billion euros ($6.8 billion,) visa-free travel for its citizens and faster-track entry into the bloc but only three billion euros ($3.4 billion) has been given and the other pledges are on hold.

The man asked not to be identified out of concern for his safety and livelihood. Two European officials, speaking on condition of anonymity because they were not authorized to discuss the case with reporters, confirmed his identity, the paper said.

The interpreter, who is originally from Afghanistan, has lived for years as a legal resident in Italy and works for Frontex as a member of an EU.-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 EU 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, without adding if he had identification.

After they were beaten, detained and forced into Turkey, the interpreter said, he managed to reach Constantinople, where he received consular assistance from the Italian authorities and returned to Italy.

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 and that when he tried to explain who he was they laughed at him and kept hitting him.

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.

That mirrors accusations from human rights groups and other refugees and migrants with the same stories, all rejected by Greek authorities who said it never happened although Turkey’s Coast Guard said it had video evidence.

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, the report added.

Prime Minister Kyriakos Mitsotakis of Greece earlier said there weren’t any abuses against migrants although acknowledging his New Democracy Conservative government has taken a hard line against them.

Johansson said she had spoken with the Greek Minister for Citizen Protection, Takis Theodorikakos, and he promised to investigate the interpreter’s claims. But while promising to probe the charges he suggested they weren’t true.

Under Greek and EU laws, authorities in countries where refugees and migrants land are supposed to assess asylum requests and keep them in humane conditions.

There have been up to 100,000 of them in Greece, including thousands on five Greek islands near Turkey’s coast, virtually all wanting sanctuary or else they would be sent back to Turkey under the swap deal.