21 people have died after two boats carrying refugees sank of the coast of Greece overnight.

18 people near the island of Kalymnos and another three died off the island of Rhodes.

The Merchant Marine Ministry of Greece has confirmed these latest fatalities, as thousands of refugees try to escape Syria and Afghanistan before the winter sets in.

AP says 18 people were killed and 138 people were rescued near the island of Kalymnos overnight - while another three died and six were rescued in a separate incident off the island of Rhodes.

Bad weather has made the already dangerous crossing between Turkey and Greece even more treacherous.

Eight people, including several children, were killed early on Thursday after a boat capsized off the island of Lesbos.