Fifty five people are dead or presumed drowned after an overcrowded refugee boat capsized off the Somali coast.

Five survivors said that the boat capsized just 15 minutes into its journey from the port of Bosasso in northern Somalia, tipping all those on board into the sea.

The youngest victim was a boy less than four years old.

It is the worst such incident in the Gulf of Aden since February 2011, when 57 Somali migrants died trying to reach Yemen, the UN High Commissioner for Refugees (UNHCR) said in a statement.

According to the UNHCR, those on the boat were Ethiopians and Somalis.

Some 23 bodies have been recovered -14 women, eight men and the boy - and the remaining passengers are presumed to have drowned.

Bruno Geddo, the UNHCR Representative for Somalia, said: "Without doubt, the Gulf of Aden is now the deadliest route for people fleeing conflict, violence and human rights abuses in the Horn of Africa."

Thousands of African migrants often use unseaworthy boats to try to reach Yemen, seen as a gateway to wealthier parts of the Middle East and the West. Hundreds die in the attempt.

The UNHCR's figures show the latest deaths bring the number of those drowned or missing in the waters between Somalia and Yemen this year to 95.

It estimates that 100,000 people have crossed the Red Sea and the Gulf of Aden this year, despite warnings about the risks.