While there are no official counts, she estimated that no more than several hundred worshipers belong to organized satanic "churches" in the United States. (Play a 1692 Salem witch-hunt interactive.)
It's hard to track satanic activity, experts say.
Lesley Bannatyne, an author of several books about Halloween, has found "no confirmed statistics, court cases, or studies to support the idea that serious satanic cult crime even exists."
"It turns out that most of the devil-worshipping activity reported in the media is perpetrated by teenagers based on what they've read in church literature or seen in movies," she writes in the book A Halloween How-To.
In recent weeks, a rash of cat mutilations in San Antonio, Texas, has garnered much attention and some speculation that the killings are linked to religious rituals.
So far five cats have been found either missing limbs or severed in half. Officials say the cuts are clean, showing that the acts are the work of an individual or group—not wild animals.
"Around this time of year, around San Antonio, there's an increased number of cats that we find mutilated," said Elizabeth Brown of the city's Animal Care Services.
The city-run shelter has had a long-standing policy of suspending black cat adoptions prior to Halloween.
Brown said the reason is to prevent cats from being harmed by religious cults or demented individuals. A recent mutilation case involved an aspiring forensic investigator who practiced on felines, she said.
Another San Antonio shelter spokesperson, Lisa Norwood, said she wasn't aware of any local cases involving cat-killing cults. However, the shelter has heard anecdotal reports of the phenomenon occurring elsewhere, she said.
"The temporary suspension of adoptions is an issue of being safe rather than sorry," Norwood added. "It's not because we expect something to happen. It's because we want to prevent something from happening."
San Antonio isn't the only city concerned about cats' safety.
A handful of shelters call the Humane Society of the United States each year asking if they should enact a similar policy.
Michael Arms, who conducts animal adoption workshops throughout the country, often gets asked the same question.
"There are a lot of organizations out there that still have this fear," said Arms, president of the Helen Woodward Animal Center in Rancho Santa Fe, California. "It's silly."
Before Arms was hired in 1999, the shelter had a no-black-cats adoption policy around Halloween.
Arms got rid of the restriction. He said a solid screening process of adopters is all that's needed to make sure the animals go to good homes.
Denying adoptions only gives the public the wrong idea about black cats, he said.
"It makes people believe these kitties are evil, and they're not," Arms said. "They're lovable."
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