How borders are drawn and enforced has far-reaching consequences, whether we live on either side of them or halfway across the world.

Syrians trying to escape from civil war and ISIL are being forcibly returned to the country, in direct contravention of international law, according to a report released yesterday (April 1).

Amnesty International, a human rights organization, claims that Turkey, which shares a long land border with Syria, is rounding up groups of hundreds of refugees and forcing them to return across the border.

International law states that people cannot be returned to a country where they are at risk of being harmed or killed, a principle called “non-refoulement”. More than 20,000 civilians were killed in Syria last year alone. The conflict has been raging since 2011.

Turkey has denied returning refugees to Syria against their will, according to the BBC. But Amnesty says the mass returns are an “open secret” in the region. The report includes testimonies from people who say they were forced back to Syria in recent months, and includes cases of children as young as nine returned without their parents.

The situation is likely to get worse. A deal signed two weeks ago between the European Union and Turkey would allow Europe to send refugees back to Turkey if they cross the bloc’s borders from that country. More than 850,000 people made the journey from Turkey to Europe last year, many via a dangerous crossing by dingy to Greece.

The deal, under which Turkey has been promised money and a fast-track to eventual EU membership, has been heavily criticized by human rights groups. The UN urged that it be scrapped unless the safety of those returned can be assured. ”It is a deal that can only be implemented with the hardest of hearts and a blithe disregard for international law,” said John Dalhuisen, Amnesty’s director for Europe and Central Asia, in the group’s report.

The return of refugees from Europe to Turkey is due to begin on Monday (April 4th).

Turkey and Jordan, both of which border Syria, have absorbed hundreds of thousands of refugees during the course of the Syrian conflict. But living conditions and attitudes towards these arrivals have deteriorated. Amnesty reports that Syrians arriving in Turkey are not being allowed to register with authorities, meaning that they can’t access even the most basic healthcare.

Those who are shipped back to Syria have few options. One is to try and live in one of the camps along the Syrian side of the border, but these often lack water, sanitation, or adequate food. Needless to say, conditions further inside the war-torn country can be even worse.