Several across the world are baffled as water in the Olympic diving pool in Rio suddenly turned dark green from its normal blue colour.
The mysterious shade of the water, which contrasted sharply against the blue hue of the water polo pool beside it, generated jokes about algae and dye on social media and overshadowed the women's 10 meter synchronised platform final.
The water had been blue on Monday and there is yet no explanation as to why it changed colour. However, according to the organisers, it is safe.
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"The water quality at the Maria Lenk Aquatics Centre was tested and there were no risks for the athletes. We are investigating the cause," officials said.
Some Twitter users also expressed bewilderment over the sudden colour change in one of the pools.
Ermmm...what happened?! pic.twitter.com/pdta7EpP2k— Tom Daley (@TomDaley1994) August 9, 2016
Omg, the pool's green?! What the hell???? It looks like Shrek's been swimming in there! 🙈🙊— Laura Davidson (@lovelylaurajd) August 9, 2016
one of these pools is...not like the other pic.twitter.com/2wJP4SyQ4t— Mina Kimes (@minakimes) August 9, 2016
What's with the super green diving pool? #Olympics2016— Hello Embo (@imhelloembo) August 9, 2016
Venue spokesman Simon Langford said water tests found "no risk whatsoever to athletes' health" Reuters reported. "We are investigating to determine what the cause of the situation was, but we are happy to report that the competition was successfully concluded," he said.
The water quality at the Maria Lenk Aquatics Centre was tested and there were no risks for the athletes. We are investigating the cause.— Rio 2016 (@Rio2016) August 9, 2016
Although some observers expressed concern, several divers told reporters after the competition that they were undisturbed by the conditions.
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Bronze medalist Meaghan Benfeito of Canada told reporters that the colour had made her and her partner Roseline Filion want to laugh, but the green actually helped. "It's not the same color as the sky so that was really on our side today."