Police nationwide are warning the public to be wary of "end of the world" scams.

The approach on Friday of so-called doomsday, based on the ancient Mayan calendar, has caused some unrest and panic-buying, according to authorities.

Last week, police in Wangcang county, Sichuan province, detained two men who were spreading information about the "end of the world" prophecy and trying to persuade residents to join a cult, China News Service reported over the weekend.

Shoppers in Shuangliu county, also in Sichuan, and Jilin provincial capital Changchun, cleared out stores' supplies of candles after rumors circulated of three days of darkness starting on Friday.

Yang Guang, an astronomer at the National Astronomical Observatories satellite observation station in Changchun, said there is no scientific reason to think the world will end on Friday.

"Dec 21 is the winter solstice and it's just the change of seasons," he said. "The day is short and the night is long, but it's a normal, natural event."

Some of the candle-buyers later said they think the rumors were aimed at undermining social order and cheating people out of their money, according to reports.

Some illegal organizations had their members spread the doomsday message and advocate people join the cults for safety, a notice from Shaanxi province's anti-cult office said on Friday.

Members of the illegal Almighty God cult recently took advantage of the much-hyped prophecy to hold illegal gatherings and disseminate doomsday information in the province, the notice said.

The Almighty God cult started in 1990 in Henan province. The organization requires members to surrender their property to the group.

On Dec 8, police in Huang-long county, Shaanxi, detained seven people on suspicion of disseminating information on a bus to scam passengers.

The province's anti-cult office urged people to resist the cult, which it said has seriously disturbed people's normal religious beliefs.

On Dec 13, police in Xining, capital of Qinghai province, detained 37 members of the Almighty God cult and seized a large amount of propaganda, a government release said on Saturday.

Police in the two provinces have urged people to call the 110 hotline if they witness criminal or cult activities.

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