"We found seven more dolphins this morning in a state of decomposition," Jasvin Sok Appadu from the fisheries ministry told Reuters.
Results from an autopsy conducted on the 17 dolphins found on Wednesday are expected on Thursday.
The spill came from the Japanese-owned MV Wakashio, which ran aground on July 25 and began to spill oil about a week later. The ship was scuttled Monday.
Greenpeace called on the government of Mauritius to launch an "urgent investigation to determine the cause of the deaths and any ties to the Wakashio oil spill".
The full impact of the spill is still unfolding, but scientists have warned of a major ecological disaster, which could impact Mauritius and its tourism-dependent economy for decades. (Reporting by Giulia Paravicini; Editing by Giles Elgood)
epa08610460 A view from the beach of Pointe D'Esny of the two parts of the MV Wakashio, a Japanese owned Panama-flagged bulk carrier after it split in two following running aground off the southeast coast of Mauritius, 17 August 2020 (issued 18 August 2020). The ship was sailing from China to Brazil when it hit coral reefs near Pointe d'Esny on 25 July 2020. Oil from the grounded ship is damaging protected marine ecosystems. EPA-EFE/REUBEN PILLAY 