Hundreds of sea turtles found floating dead in the waters off El Salvador were killed after eating microalgae, scientists said on Friday.

Between 300 and 400 decomposing sea turtle bodies washed up in Jiquilisco Bay around November 1, prompting biologists with the University of El Salvador and experts with the Environment Ministry (MARN) to investigate the case.

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Officials said during a press conference that the creatures were poisoned by "saxitoxins," or potent neurotoxins that lead to paralysis, linked to a so-called red tide algal bloom.

They noted that the microalgae mainly affected the liver and intestines of the turtles, but the total number of deaths remains unclear.

The scientists and ministry experts said that the surge of microalgae was caused by Tropical Storm Selma, which hit El Salvador at the end of October.

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The wind pressure caused by the storm agitated the seabed, raising sediment that caused a rapid expansion of the toxic microalgae.

The Environment Ministry also noted that the turtles could have died elsewhere and then been carried by ocean currents to Jiquilisco Bay.

rs/rc (dpa, EFE)