At least 6,618 migrants died or disappeared while trying to reach Spain by sea in 2023, an average of 18 per day, a Spanish migrant rights group said Tuesday.

The figure is almost three times the number recorded in the previous year -- 2,390 -- and the highest since Caminando Fronteras, or Walking Borders, began keeping a tally in 2007, its coordinator, Helena Maleno, told a news conference.

The total includes 384 children, according to the organisation which compiles its figures from families of migrants who died or went missing and official rescue statistics.

The vast majority of the deaths and disappearances -- 6,007 -- took place on the Atlantic migration route from Africa to Spain's Canary Islands.

With controls tightening in the Mediterranean, the seven islands have become a favourite destination for people fleeing poverty and conflict in Africa, mostly on overcrowded, barely seaworthy vessels that lack enough food and water for the journey.

"The Atlantic route has become the deadliest route in the world," Maleno said.

She blamed the rise migrant deaths and disappearances last year on a lack of means for rescuers and a surge in the number of attempted crossings to Spain.

The number of migrants arriving illegally in Spain in 2023 nearly doubled from the previous year, reaching 56,852, according to interior ministry figures, the most since 2018 when 64,298 migrants entered the country.

The majority, about 70 percent, arrived in the Canary Islands, which are barely 100 kilometres (60 miles) from the northwest coast of African at their closest point.