A wooden refugee boat has crashed with a patrol ship during a rescue operation near the Aegean island of Lesbos, leaving eight people missing, according to Greece's coast guard. An official from the coast guard said 31 people on board were rescued.

The boat collided with the patrol boat due to rough seas and winds before capsizing and sinking about half a nautical mile north of Lesbos. The island has been a major entry point for those making the journey from the nearby Turkish coast.

The incident took place as European leaders are looking to strike a deal with Turkey to try and stop the flow of migrants to Europe. The agreement will include EU support for handling migrants, helping with the coast guard effort to rescue floundering vessels, and combating people smuggling operations.

Negotiations for the deal were already well under way when Turkish President Recep Tayyip Erdogan visited Brussels in early October. Under the proposed plans, refugees and migrants picked up on their way to Greece and its islands of Kos, Lesbos, Samos and Chios would be returned to Turkey. They would then be housed in camps for up to two million people, which would be built and co-financed by the EU, to relieve the huge pressure on Greece in particular.

To deal with the extra Syrian refugees Turkey could open six refugee camps for 2 million more individuals. Turkey already houses two million refugees from the Syrian conflict within its borders.