Kazakhstan Sleepy Hollow Kalachi
Kazakh town evacuated over mystery sleep disorder wikimedia commons

The Kazakh town of Kalachi is being evacuated by authorities over a mysterious sleep disorder which makes people fall asleep at random.

Officials are perplexed over the cause of the disorder which has reportedly been in existence since 2010.

The town has been nicknamed "Sleepy Hollow" after the bizarre phenomenon.

Two other towns in the region have also been hit by the epidemic, which experts suspect could be due to a condition called "encephalopathy".

Apart from falling asleep at random, people have also reported frequent memory loss and dizziness while some reports claimed hallucination as well.

Local reports suggest some of the people remain in sleep for as long as two days while others speculate a few animals are also affected.

With no success in finding a cure for the disorder, authorities have recommended evacuation of the town which has a population of less than 1,000.

"Carbon monoxide is definitely a factor. But I can't tell you whether this is the main and vital factor. The question is why it does not go away. We have some suspicions as the village has a peculiar location and weather patterns frequently force chimney smoke to go down instead of up," Sergei Lukashenko, the chief of Kazakhstan's National Nuclear Centre's Radiation Safety and Ecology Institute, told the Siberian Times.

There was also speculation that the radon emerging from a nearby uranium mine was the culprit.