Nearly 50 migrants from West Africa died off the coast of Mauritania this week, when their boat became stranded as they tried to make the dangerous and illegal crossing to Europe.   The incident is one of the worst this year.  Selah Hennessy reports from the VOA West Africa bureau in Dakar immigration officials say the number of people attempting the dangerous crossing appears to have gone down.

Mohamed Ould Hamada is head of the Mauritanian branch of the Red Cross.

He says four people have died since the rescue mission Tuesday, and another eight are in critical condition in hospital.

He says the migrants are from all-over West Africa, but especially from Senegal.  He says many are very young, some as young as 12.

Local journalist Salem Bokari says the boat departed from southern Senegal more than two weeks ago, with almost 150 passengers on board, and was headed to the Canary Islands.  He says the boat suffered engine failure last week off the coast of Morocco.

He says those who died had suffered from thirst, hunger, and hypothermia.  

London-based Africa analyst David Hartwell says a major effort is being made by the United States and the European Union to stem the tide of illegal migrants to Europe.

He says Spain especially, a popular landing point, has increased its fight against clandestine migration in recent years.

Hartwell says Madrid has signed cooperation and repatriation agreements with numerous African countries, including Morocco, Mauritania, and Senegal.

"They have mounted obviously additional patrols and they are taking a more pro-active stance around the Canaries and around their own coast-lines; more coast-guard patrols; more high-tech scanning equipment, that kind of thing," he said.

But he says the main problem lies with African countries themselves, who do not have the resources or infrastructure to combat illegal migration; and who have failed to cooperate on a regional basis to solve the problem.

"The security forces within these countries are in general very, very poorly equipped to be able to meet the challenge posed by long porous borders, desert terrain; and the lack of meaningful cooperation on a regional level, and even on a slightly wider level, is a major, major obstacle also to effectively tackle the problem," he added.

He says the fight against illegal immigration does, nonetheless, seem to be making progress.

According to surveillance experts, there has been a 60 percent decrease in the number of African migrants arriving in the Canary Islands during the first sixth months of this year, as compared to the same period in 2006.