Turkey on Monday accused Greece of pushing a boat carrying migrants out of Greek territorial waters and back into Turkish ones.

The defence ministry in Ankara said the incident occurred on Sunday near Rhodes, and posted drone footage on social media that it said showed the coast guard pulling the boat into Turkish waters near the southwestern resort of Marmaris.

The Greek coast guard had no immediate comment.

Reuters was not immediately able to verify the authenticity of the footage, which shows the occupants of one boat attaching a rope from its stern to a small rubber dinghy, which the boat then tows in reverse before detaching from it and moving off. It was not clear how many people were in the dinghy.

Athens has repeatedly denied accusations by rights groups and United Nations refugee agency UNHCR that it pushes migrants out of Greek waters, saying it intercepts boats at sea to protect its borders.

Greece was the frontline of Europe’s migration crisis in 2015 and 2016 when around a million refugees fleeing war and poverty in Syria, Iraq and Afghanistan arrived, mainly via Turkey. The number of arrivals has fallen sharply since then.

Greece and Turkey, NATO member states and historic rivals, have long been at odds over migrant issues and competing territorial claims.