Officials in Peru said Thursday they are investigating what caused the deaths of nearly 900 dolphins that have washed up on its northern coast over the past four months.
Authorities said they suspect a virus may be responsible, but are awaiting test results to know whether they can rule out environmental pollution or other factors in the deaths of the marine mammals.
"So far that's the most likely hypothesis," Deputy Environment Minister Gabriel Quijandria told local radio.
Ninety-five percent of the deaths affected bottlenosed dolphins, which since January have washed up along a 170-kilometer (100-mile) stretch of coastline.
"It's not the first time this has happened. There have been other instances in Peru, Mexico and the United States," Quijandria added.
In those cases, he said, the deaths were attributed to outbreaks of highly infectious morbillivirus, related to ailments such as rinderpest, measles and distemper, an easily transmittable disease affecting dogs.
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