Investigations are on into the deaths of hundreds of dolphins that washed up on the northern coast of Peru. Around 877 carcasses of dolphins and porpoises were found on Peruvian beaches in two and half months. Peruvian officials and environmentalists are trying to unravel the mystery behind the phenomenon.

No concrete reasons have been figured out yet but the authorities believe that it could possibly be a viral infection that may have killed the dolphins in huge numbers. While environmental groups in the country blame the seismic oil exploration work carried out by BPZ Energy Company for the dolphin deaths.

The most probable hypothesis is the possibility of an infection with a virus, he said. There are scientific articles about the incidence of morbillivirus, a type of distemper, in cetaceans in Peru, and that can be ruled out or proven next week, told Deputy Environment Minister Gabriel Quijandria to Associated press.

BPZ, a Houston-based company had carried out the oil exploration work between February 8 and April 8, off Northern Peru. Peruvian environmentalists have said that the sound waves generated from the oil exploration work could be the cause of the deaths.

However, Quijandria said that so far there is no proof to link dolphin deaths to seismic work, according to the Associated Press report.

Most of the carcasses found were already decomposed, making it difficult to study the cause of their deaths. However, authorities have also ruled out the possibility of deaths due to lack of food or poisoning, CNN reported quoting Andina News Agency.

Mass dolphin deaths have been reported globally in recent years, raising concerns about the survival of the species.