At least 25 people, mostly children and teenagers, have been killed in a bus crash on Fogo Island in Cabo Verde, according to the country’s public radio network RCV.

The crash happened on Saturday as the bus, carrying 32 passengers, was returning to the city of São Filipe after an excursion to Chã das Caldeiras, a village located inside the crater of the Pico do Fogo volcano.

The bus reportedly veered off the road and plunged into a deep ravine, coming to a stop in a rocky valley that is difficult to reach.

The dead include the bus driver, who organised the annual excursion as a gift for pupils he drove to school during the school term.

Emergency personnel worked through the night to rescue people trapped in the wreckage. Several others were injured, some seriously, according to José Canuto, head of civil protection in São Filipe.

Seven victims were buried early on Sunday, while the remaining victims were expected to be buried later in the day, RCV reported.

Local authorities have not yet provided further details on what caused the crash.

Fatal road accidents are relatively uncommon in Cabo Verde, where roads are generally considered to be in good condition.