Nigeria, Feb. 9 -- Like a scene from the ancient plague that rocked the River Nile in Bible times, the Sarandi Stream in Argentina has turned a shocking shade of blood red, leaving residents alarmed and authorities scrambling for answers.

The canal, which flows into the Rio de la Plata, mysteriously changed color on Thursday, February 6, accompanied by a strong, pungent odor that woke up locals in Avellaneda, a suburb 15 kilometers (9 miles) south of Buenos Aires.

"It looked like a river covered in blood. It's horrible," said Maria Ducomls, a longtime resident, in an interview with AFP.

"The smell woke us up. In the daytime, when we looked at this side of the river, it was completely red, all stained."

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