Ankara, September 21 (RHC)-- At least 13 refugees have been killed after a boat on its way to Greece collided with a ferry off the coast of Turkey. The Turkish Dogan News Agency said the incident took place after the inflatable boat carrying 46 refugees collided with a ferry, on Sunday. Four children were reportedly among the dead whose nationalities remain unknown.

The boat had been on its way from the northwestern Turkish port of Canakkale to the Greek island of Lesbos. According to the report, 20 people were rescued after they were spotted by a European Union helicopter.

The boat was the second to sink on Sunday in the Aegean Sea. The Greek coastguard said another two dozen people are feared missing from another similar incident near Lesbos.

Lesbos has in recent weeks received a wave of Syrian refugees fleeing violence in their country, with many risking their lives while attempting to cross the Mediterranean Sea.

The Office of the United Nations High Commissioner for Refugees (UNHCR) said over 442,440 refugees have arrived in Europe via the Mediterranean so far this year, 2,921 of whom have reportedly lost their lives during the perilous journey.

Most of the asylum seekers are reportedly fleeing conflict-hit zones in Africa and the Middle East.