More than 300 endangered sea turtles were found dead near the southern coast of Mexico, the country’s environmental officials said.

It appears that hundreds of Olive Ridley (Lepidochelys olivacea) sea turtles died after they became entangled in an illegal fishing net off the coast of La Barra de Colotepec, Mexico’s federal agency for environmental protection said Tuesday.

The government’s special prosecutorial office for crimes against the environment (PROFEPA) and other agencies are working to find those responsible for the incident.

The dead sea turtles have since been removed from the water and buried in order to avoid any further contamination.