Updated

The world's biggest animal slaughter is once again under way. The Guardian and Al Jazeera report on the weeks-long festival, which takes place every five years in the Nepalese village of Bariyapur.

The killing takes place over just two days, in this case, Friday and Saturday: Hindus armed with curved kukri knives kill mass quantities of animals—as varied as buffaloes, goats, and rats—in honor of Gadhimai, the goddess of power.

As the centuries-old legend goes, she came to a prisoner in a dream and asked that he build a temple to her; he awoke to find himself no longer bound.

As the story goes, he then built that temple, and sacrificed animals there. Today, worshipers believe the sacrifice will bring them prosperity, and that eating the dead animals will keep evil at bay.

The festival's last occurrence, in 2009, saw an estimated 300,000 animals killed, either by decapitation or by having their throats slit. That makes it the biggest mass killing of animals at a single site, says Al Jazeera.

The festival begins with the ritual killing of five animals: a goat, rat, chicken, pig, and pigeon; buffaloes are then slaughtered throughout the first day. It attracts a million worshipers, and in recent years, it's also attracted the scorn of animal-rights advocates, who say the untrained butchers cause a great deal of suffering and see the piles of dead animals as a health concern.

The director of the Indian branch of the Humane Society International describes the scene: "Pools of blood, animals bellowing in pain and panic, wide-eyed children looking on, devotees covered in animal blood, and some people even drinking blood from the headless but still warm carcasses."

This article originally appeared on Newser: World's Biggest Animal Slaughter Has Begun

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