ARGUINEGUIN, Spain — Five migrants were found dead aboard a boat rescued off Spain's Canary Islands, maritime rescue authorities announced Thursday. Three survivors were airlifted to a hospital in serious condition.

Another 41 individuals disembarked at the port of Arguineguin on Gran Canaria early Thursday after the rescue operation. A rescue aircraft spotted the vessel Wednesday approximately 65 nautical miles southwest of Arguineguin.

Helena Maleno, founder of the migrant rights group Walking Borders, said survivors reported a much higher death toll. According to these accounts, 83 people, including three women and a baby, died during the crossing.

The boat departed from The Gambia 27 days before its rescue. Maritime Rescue confirmed only that five bodies were aboard the vessel when rescuers reached it. Adverse weather conditions prevented the recovery of these bodies.

Fernando Clavijo, president of the Canary Islands regional government, called for a national migration policy following the tragedy. Clavijo cited a deadly migrant surge in Spain's North African enclave of Ceuta in July as further evidence of the need.

"It is intolerable that lives continue to be lost," Clavijo said on X. "The Canaries cannot get used to or accept as normal the fact that the Atlantic continues to be a death trap."

The Atlantic route from West Africa to the Canary Islands is among the world's most perilous migration crossings. Thousands attempt the journey annually in overcrowded boats, facing rough seas, strong currents and extended distances.

Official data shows arrivals of migrants reaching the Canary Islands from West Africa have fallen 57.4 percent so far this year compared with the same period last year.