Photo:Italian Firefighters (Vigili del Fuoco) / Handout/Anadolu Agency via Getty

part of water of Grand Canal appeared to have turned bright green as the Rialto Bridge is seen in Venice

Italian Firefighters (Vigili del Fuoco) / Handout/Anadolu Agency via Getty

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, reportedCNN.

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

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, perCBS News.

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STRINGER/ANSA/AFP via Getty

fluorescent green waters below the Rialto Bridge in Venice’s Grand Canal.

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.

ANDREA MEROLA/EPA-EFE/Shutterstock

Phosphorescent green patch appears on Grand Canal in Venice

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.

source: people.com