Russian authorities are investigating the mysterious death of nearly 300 endangered seals that had been discovered washed up on the shores of the Caspian Sea. 272 dead Caspian seals have been found at a number of locations in the southern region of Dagestan.

130 dead seals washed up in Russia's Lake Baikal, and scientists have taken lake water samples and biopsies of the animals. Preliminary theories about the die-off did not suggest pollution is the reason.