Russian officials have admitted that a once-pristine beach in a remote area of the country may have been contaminated with toxic chemicals after activists declared an "ecological disaster" and filmed dozens of dead sea creatures.
Greenpeace said that sea pollution in the eastern Kamchatka peninsula had devastated the local wildlife population and left surfers and divers with damaged eyesight and poisoning symptoms.
Last week local social media users posted videos of a yellow-tinged sea and tourist hotspot Khalaktyrsky Beach, popular with surfers, strewn with dead sea urchins, octopuses, seals and fish.
Locals report an area as large as 25 miles has been affected, with hundreds of creatures killed.
Regional governor Vladimir Solodov said the pollution could have been caused by "spills of some toxic substances".
Inspectors are due to examine two local military testing sites on Tuesday.
"There are concerns; we will fully examine this tomorrow," Mr Solodov said, adding that the local government is also examining potential natural causes related to algae and “seismic activity”.
He said divers have confirmed the mass deaths of sea creatures, but tests on the water flowing from a river into a bay did not show pollution levels above legal levels.
Tourists had been urged not to visit a live volcano on Kamchatka, with authorities warning that eruption could be imminent.
But local ecologists said that the crisis was unlikely to be caused by natural activity, pointing instead to an area nearby used to dump chemical waste.
🎥 @lefffu Мой любимый Океан погибает... Осьминожки Дофлейна... А вы знаете, что у них 3 сердца и любят они один раз за всю свою жизнь! Они умные, любопытные и у них есть глаза! Очень жаль, что я пишу о них сейчас, когда каждый день на Тихоокеанское побережье Камчатки выбрасывает десятки трупов этого фантастического создания! А мы не знаем, почему🤷🏻♀️ и как им помочь! Самое ужасное в жизни - это беспомощность. И жители Камчатки уже столкнулись с этим. Кто-то не осознает, кто-то закрывает глаза, кто-то не верит... но, так или иначе, всех это коснется! 😓 @vv_solodov @_svetlana__radionova_ @greenpeace @greenpeaceru
A post shared by Kristy Fury (@kristy_rozenberg) on Oct 2, 2020 at 1:17am PDT
Greenpeace raised the alarm after local surfers said they had been suffering from nausea and vision problems after leaving the water for some weeks. Several people suffered corneal burns, Mr Solodov said.
Vasily Yablokov, head of the Greenpeace climate project in Russia, said the situation was a threat to the region's tourism industry.
"It is necessary to contain and prevent further pollution of the coastline as soon as possible, identify the source of pollution and take the necessary response measures," he said.
The organisation said that tests showed that petroleum oil content in the water was four times higher than it should have been, and the content of toxic chemical phenol was two and a half times too high.
In a Facebook post last week, Ekaterina Dyba, of local surfing school Snowave Kamchatka, said that military exercises had been carried out in the area but the source of the pollution was not clear.
"It was hard to imagine that environmental trouble would come to my house on the edge of the world," she wrote.
The Russian military has denied that its Pacific Fleet is at fault, stating that no drills involving heavy equipment had been held at the local range since June.
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