#Venice’s Grand Canal Mysteriously Turns Fluorescent Green: Photos

Something out of the blue happened in Italy over the weekend.

The water along a stretch of the famed Grand Canal in Venice mysteriously turned bright green on Sunday, prompting Venetian authorities to launch an investigation into what happened, reported CNN.

Local residents were the first to report the strange color, Luca Zaia, governor of the Veneto region, wrote on Twitter.

“This morning a patch of phosphorescent green liquid appeared in the Grand Canal of Venice, reported by some residents near the Rialto Bridge,” he wrote, per CNN. “The prefect has called an urgent meeting with the police to investigate the origin of the liquid.”

Images posted to social media showed the famous embankment, which is lined with restaurants, glowing green as tourists snapped photos — and gondoliers carried on with business as usual, per CBS News.

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The Italian fire service immediately took samples of the water as officials reviewed CCTV footage and questioned the gondola drivers on whether they had seen anything, per CNN

Police are also looking into if climate change activists had a hand in the change, according to local outlet La Nuova Venezia, reported CBS News.

Something similar occurred in 1968, when Argentine eco-artist Nicolas Garcia Uriburu poured a green dye in the same area of the Grand Canal to promote environmental awareness, per CNN.

So far, no groups have claimed responsibility for the change in the water on Sunday, according to the outlet.