BEIJING — Much like in the rest of the world, the coming "doomsday" supposedly preordained by the Mayans to strike earth Friday at the end of a 5,125-year calendar has been something of a running joke in China.

The subject this week has been easily a top-10 trending topic on China’s Twitter-like service, Weibo, with users sharing hundreds of thousands of jokes, cartoons and other comments about the end of days.

One popular doomsday cartoon shared by Taiwanese alternative rock singer Ashin, showing a mock weather report predicting fire and brimstone for Friday, was forwarded more than 109,000 times and drew almost 25,000 comments.

Not everybody thinks the end of the world is funny, though. A poll conducted by Ipsos-Reuters in 21 countries earlier this year claimed that as much as 20 percent of China’s population believed that the Mayan calendar correctly predicted this month as the end of the world. That percentage was markedly higher than in the second country on the list, Turkey (at 13 percent), or in the United States (12 percent).

The government is taking one aspect of the doomsday talk seriously; it has reportedly rounded-up members of a religious group calling for the toppling of the Communist Party. 

The group, known as the “Almighty God,” has called for a "decisive battle" to slay the "big red dragon," a reference to the Book of Revelation and the organization’s name for the Chinese Communist Party.

Nearly 1,000 members of the sect have been arrested, The New York Times reported. NBC News could not independently verify the number of detentions, but Chinese state media also reported that authorities had detained around 1,000 members over some seven provinces, Reuters reported.

This is not the first time that China has dealt with a fast-moving Christian cult it deems a risk to party rule. In fact, according to the newspaper, “Almighty God” has its roots in a sect that claimed it had 300,000 adherents called "Lightning from the East," according to Time Magazine in 2001.

Lightning from the East propagated the belief that Jesus had returned to earth in the form of a 30-year old Chinese woman who had written a third testament of the Bible and promised salvation from the coming apocalypse for all who joined her.

AFP - Getty Images, file

Lu Zhenghai of Xinjiang said he wasn't necessarily worried about "doomsday," but he thought "something" bad would happen today. So he built this ark.

Money from fear
Many Chinese, meanwhile, have seen opportunities to cash in on the apocalyptic mania.

After watching the Hollywood disaster film "2012," in which China leads the way in building arks to save the rest of the world, Liu Qiyuan, a former furniture maker living just outside Beijing, began conceptualizing scaled-down arks that could be marketed to consumers equally concerned about the end of days.

With the help of 10 workers, Liu designed and built metal spheres covered in fiberglass and fitted with an on-board engine. Supposedly strong enough to handle a battering from a catastrophic tsunami or earthquake, the capsules are designed to house 14 survivors and enough food and water for five months at sea.

The cost of such peace of mind is $50,000 each. Even if the end of the world does not come Friday, Liu is optimistic that he will recoup his reported $288,000 investment by marketing his life capsules to China’s navy.

One man who has gone all-in on his disaster convictions is Lu Zhenghai from China’s far western province of Xinjiang. For the past two years, Lu has been working to build an ark measuring 65 feet and weighing around 80 tons that could comfortably hold 50 people and a two-year stock of food and medicine.

"I don’t believe in the doomsday, but I do believe something is going to happen on December 21st," Lu told NBC News, "I don’t know what could happen and where, but I want to be ready just in case."

Having left his job, cashed-in his savings and sold his apartment to help pay for this family refuge, Lu has been living at his parents’ home with his wife and daughter as he makes final preparations on the ark. The vessel has already cost over $240,000 to build.

Though Lu talks happily about progress on the ship, he seems far more excited to talk about the media attention and visitors his ark has been attracting.

"Hundreds of people have come to see my ark," Lu said, adding that a Hong Kong television station was planning to film the ark, presumably mere moments before disaster strikes the earth.

NBC News’ Yanzhou Liu contributed to this report.

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