SANTA CRUZ DE TENERIFE, Spain (AFP) - An international air and sea rescue continued to search for 50 would-be immigrants feared drowned off the Canary Islands after their boat capsized, Spanish rescue services said yesterday.
Rescue services added that two rescue boats that had earlier picked up 48 survivors were headed back to port at Puerto de los Cristianos on Tenerife.
"We are still searching," an island official told AFP.
Statements from some of the 48 survivors said there were around 100 people on the vessel when the accident happened, said a statement from Salvamento Maritimo, the sea rescue organisation.
"The Luz de Mar and Conde de Gondomar maritime rescue vessels this morning saved 48 people aboard a cayuco (an African-style fishing boat) after it sank," a rescue services said in a statement.
The accident occurred early Thursday about 100 nautical miles southwest of Tenerife "owing to poor conditions at sea amid three-metre (10-feet) waves and winds gusting at 30 knots," the statement said.
A spokesman for the local administration in the Canary island of Tenefire confirmed that survivors had spoken of about 100 people on board and that 48 people were rescued.
The rescue operation involved four Salvamento Maritimo ships, two planes, two helicopters and merchant ships.
French military officials in Paris confirmed that one of their vessels, the "Tonnerre", had also joined the rescue operation at the request of the Spanish authorities. The ship had several helicopters and a hospital aboard.
Civil guard director general Joan Mesquida told Spanish National radio the boat had first been spotted by a Spanish airforce plane, prompting the sending of a rescue vessel to the scene.
Given the poor weather conditions, a second vessel went to help the immigrant boat.
Mesquida said those stranded on board were clearly frightened by the size of the waves and the high winds.
The Canary Islands have been a magnet in recent years for mainly sub-Saharan immigrants.
More than 31,200 immigrants arrived in the Spanish archipelago last year, more than tripling the previous annual record and overwhelming the island chain's authorities.
More than 250 would-be immigrants have reached the islands since Sunday with some 4,700 arriving since January, despite tighter surveillance of the African coastline in recent months by the EU border patrol agency, Frontex.
The would-be immigrants risk life and limb making a hazardous voyage of several hundred kilometres in boats that are rarely sea-worthy.
An unknown number have died in the attempt, with some estimates putting the death toll in the hundreds.
Over the past two years the number of mainly sub-Saharan refugees looking to reach the Canaries has grown exponentially.
Spain and Morocco tightened cooperation in an effort to reduce the number of people trying to cross the Gibraltar Strait dividing Spain from the North African coast.