Locals in the Chinese city of Wenzhou woke up Thursday puzzled to find that their river was blood red.

Na Wan told NBC:

A few people that were up and about at 5 a.m. said that everything was normal but then suddenly within the space of a few minutes the water started turning darker and eventually was completely red.
The really weird thing is that we have always been able to catch fish and you can even drink the water because it’s just normally so good. Nobody has any idea how it could have ended up being polluted because there are no factories that dump anything in the water here.

There’s one idea circulating, reports the Voice of America:

Wenzhou is a center for commerce on China’s eastern coast.  It is also a center of Christian faith in China and is often referred to as China’s Jerusalem.  After the river water turned red some residents posted on social media that the crimson waters were a sign of Armageddon — an event described in the (Christian) Bible as marking the end of the world.

That may not be true. ABC reports that while the Wenzhou Environmental Protection is still investigating, water samples indicate the color is a due to illegal dumping.  Jianfeng Xiao, chief of the bureau told China News that the river is home to a food coloring company, a paper manufacturer, and clothing-maker.

Xiao continued:

“We suspect that somebody dumped artificial coloring in the water because he thought the typhoon yesterday would cause heavy rain, and nobody would notice [the color]. … It turned out there wasn’t heavy rainfall yesterday, so the evidence is left behind.”

This is not the first “blooding” of a river in China. The Yangtze River turned red in 2012. That turned out to be caused by illegal dumping.