Patrol boats and helicopters are searching for 48 refugees and migrants missing after their boat sank near the Spanish island of El Hierro, but officials say hopes of finding survivors are fading.

Nine people, one of them a child, have been confirmed dead after the incident in the early hours of Saturday morning, emergency and rescue services said. Rescuers were able to pick up 27 of 84 people who were trying to reach El Hierro, the westernmost of the Canary Islands.

A spokeswoman for the Canary Islands government told Reuters news agency on Sunday that the search continues “but it seems that the chances of finding someone alive are slim”.

Canary Islands regional President Fernando Clavijo had told journalists on Saturday night that the 48 people missing are “presumed dead”.

More bodies will likely appear “over the next two, three days”, washed up by the current, he added.

People on the boat were from Mali, Mauritania and Senegal, Spanish authorities said. They set out from Nouadhibou in Mauritania, some 800km (nearly 500 miles) away.

Boat sinks during rescue attempt

Shortly after midnight on Saturday, Spanish emergency services received a call from the boat, which was located about four miles (6.5km) east of El Hierro.

It sank during the rescue attempt, they said, with wind and poor visibility making the rescue extremely difficult.

“After what happened yesterday and if the forecast for the arrival of the migrant boats happens, then it will be the biggest humanitarian crisis to happen to the Canary Islands in 30 years,” Canary Islands Minister of Social Welfare Candelaria Delgado told reporters on Sunday.

Three of those rescued suffered from hypothermia and dehydration, rescue services said.

The nine who died will be buried on Monday and Tuesday. Among the dead was a child aged between 12 and 15, according to the NGO Walking Borders, which helps refugees and migrants.

As hopes of finding more survivors diminished, police installed a morgue on El Hierro, authorities said.

Three other boats reached the Canary Islands during the night, carrying 208 people.

This disaster follows the deaths of 39 people in early September when their boat sank off Senegal while attempting a similar crossing to the Canaries, from where they apparently hoped to reach mainland Europe.

In some 30 years of refugee and migrant crossings to the islands, the deadliest shipwreck recorded to date occurred off the island of Lanzarote in 2009, when 25 people died.