Authorities in the Cape Verde islands are waiting for experts from Spain to help determine why more than 100 dolphins died on a local beach.

Local media reported that around 200 melon-headed dolphins were found on a beach on Boa Vista island on Tuesday.

Officials, residents and tourists on the island off west Africa managed to drag some of them back out to sea, but many returned.

Bulldozers buried 136 dead dolphins.

Telejornal de Espanha resalta o arrojamento na Boa Vista. Video de Elton Neves. O arrojamento inicial foi de 163 animais dos que morreram 136

Posted by Bios.cv on Friday, September 27, 2019

BIOS Cape Verde, a volunteer environmental association in the former Portuguese colony, said on its Facebook page that it took samples from 50 dolphins and four others were placed in deep freeze by the local council.

The group said vets from the University of Las Palmas in the Canary Islands are due in the coming days to perform tests.