HARGEYSA: At least 10 migrants died and 30 went missing when the boat smuggling them from Somalia to Yemen suffered an engine failure in the Gulf of Aden, officials said Sunday.

Seventy people, mostly Ethiopians, were rescued when the coastguard in the northern breakaway state of Somaliland's Sanag region spotted the boat drifting towards the shore.

"The rescued passengers told us that the boat was carrying around 110 migrants when it left," Said Ige Mohamed, the head of immigration for Sanag province, told AFP by phone.

"Unfortunately, 10 were confirmed dead and 30 others are still missing in the sea," he said.

Mohamed explained that the migrants presumably spent several days huddled inside the small boat with nothing to eat or drink and apparently jumped into the water upon seeing the coast.

Two were found already dead on the boat but at least eight others drowned as they attempted to swim to the shore, Mohamed explained.

"We don't have many details. I don't know how many days they spent on the boat but the survivors told us they were headed to Yemen and left from Bosasso" in the neighbouring semi-autonomous state of Puntland," he said.

"Most of them are in serious condition and risk not making it if they don't receive urgent medical attention," the official said.

Abdullahi Awale, a security official in the Somaliland capital Hargeysa, said the incident was being investigated.

According to the UN refugee agency, the number of migrants fleeing the unstable Horn of Africa and arriving in Yemen rose by 50 percent in 2009, reaching a record high of 74,000.

The number of Ethiopians making the journey across the Gulf of Aden or Red Sea -- a route described by the UN as "the busiest and deadliest in the world" -- doubled in 2009, while the number of Somalis remained steady.

More than 300 people drowned or did not survive the trip last year.