At least 69 people have died and many others remain missing after a boat capsised off the coast of Mauritania, according to the country’s coastguard.

17 individuals have been rescued, while search operations continue for additional passengers who had been aboard the wooden canoe, which was bound for Spain’s Canary Islands.

Survivors reported that the vessel departed from The Gambia six days prior to the accident, which occurred on Tuesday. Approximately 160 people were on board, most of whom were Gambian and Senegalese nationals.

The Atlantic route to the Canary Islands has become increasingly used by African migrants attempting to reach Europe. Nearly 47,000 people arrived in the Canary Islands last year. The Spanish non-governmental organisation Caminando Fronteras estimates that more than 9,000 migrants died while attempting the crossing.

Coastguard officials informed the Spanish news agency EFE that search efforts were ongoing approximately 60 km north of Nouakchott, Mauritania’s capital. Divers had been deployed to inspect the sunken vessel.

According to a senior coastguard officer, the migrants saw the lights of a coastal town late on Tuesday and shifted to one side of the boat, which caused it to overturn.

Helen Maleno, spokesperson for Caminando Fronteras, urged the coastguard to maintain the search operation. She described the incident in Spanish media as one of the most severe “tragedies of this summer”.

Earlier in the week, Mauritanian security forces were accused of systematically mistreating migrants from other African countries. A report by Human Rights Watch claimed the abuses had worsened following an agreement between the European Union, Spain and Mauritania aimed at limiting dangerous sea crossings to the Canary Islands.