Aliens? Cold? Hundreds of sheep walk in circles for days in China and no one knows why

Screengrab from the People's Daily's video

Hundreds of sheep walked in circles for days in China with no explanation, a video shows. The mysterious sight has drawn many questions and speculations.

The sheep in the northern Chinese region of Inner Mongolia walked in an endless circle for over 10 days, the People’s Daily reported along with a video on Wednesday, Nov. 16.

“The reason for the weird behavior is still a mystery,” the People’s Daily said in a tweet. But that has not stopped people from speculating.

“They’re keeping warm from the freezing cold,” one person commented on Twitter.

Aliens,” another user wrote.

Although veterinary professionals have not commented on this particular flock of sheep, a bacterial infection known as Listeriosis or Circling Disease could be the culprit. Circling Disease can infect a wide range of animals, causing them to “propel themselves into corners, lean against stationary objects, or circle toward the affected side,” the Merck Veterinary Manual explains.

While that explanation remains unproven, some people had even less likely theories for the behavior.

NASCAR fans, obviously,” one Twitter user said.

Others found the behavior “ominous,” with one commenting, “The end is here!”

One Twitter user found the sheep’s behavior much more innocent, saying “boys will be boys.”

Inner Mongolia is a region in northern China that borders the nation of Mongolia.

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