At a Glance

A river in Andorra, Spain turned an odd shade of bright green on Thursday.Authorities reassured residents, telling them the river was dyed as part of an investigation.

Residents in Seu d'Rugell, Spain were greeted Thursday by an unusual sight — the Valira River had turned abright shade of green.

According to authorities, the river that flows down the PyreneesMountains in the northeasternregion of Andorra was intentionally dyeda surprising shade of green as part of an investigation at a water bottling plant.

, a Spanish news site, said Albert Batalla, the mayor of Seu d’Urgell, reassured surprised residents, sayingthe green dye was “entirely harmless, non-toxic and biodegradable.”

also confirmed the dye was used to help identify the source of a possible contamination and "was safe for both people and the environment."

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The bottling plant was identified last year asthe source of a gastroenteritis bug that affected thousands of people across Catalonia in northeastern Spain. The victimsreportedly drank contaminated water from office water coolers that originated from the plant, The Local reported.

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