Hundreds of thousands of Hindus gathered at a temple in southern Nepal on Tuesday for a ceremony involving the slaughter of more than 200,000 animals, a festival that has drawn the ire of animal-welfare protesters.
A Nepalese minister said it was the largest sacrificial slaughter of animals in the world.
Animal rights groups and activists including the actress Brigitte Bardot have condemned the event, which takes place every five years in the Nepalese village of Bariyarpur, Sky News reported.
But Nepal's government says it will continue with the "centuries-old tradition" and will deploy armed police to keep the peace, Sky News reported.
Protests have occurred in recent weeks in towns near the Gadhimai temple and in the capital Katmandu by animals rights activists and other religious groups. However, Hindu organizers refused to halt the slaughter saying it was a centuries-old tradition.
"People have deep faith in the goddess and they believe that sacrificing animals will bring them good luck and prosperity for their families," said Mangal Chaudhary Tharu, a priest at the Gadhimai temple, according to Sky News.
"I don't think the mood will be spoiled by the animal rights campaigners. They have the right to raise their concerns."
More than 200,000 buffaloes, goats, chickens and pigeons will be killed Tuesday and Wednesday at the temple in the jungles of Bara district, about 100 miles south of Katmandu, to honor the Hindu goddess Gadhimai.
"Thousands of terrified buffaloes will have their heads cut off by drunken devotees," said Bardot, according to Sky News.
"I have dedicated my life to protect animals and the best gift I could receive for this lifelong struggle would be the announcement of the stopping of ritual sacrifice."
Pressure group Animal Nepal claims the festival represents "extreme cruelty," Sky News reported.
Chief government administrator in the area Taranath Gautam said hundreds of thousands of people began lining up in the early hours of Tuesday, and the animal sacrifice rituals had started.
The Gadhimai festival is celebrated every five years. Participants believe sacrificing the animals for Gadhimai will end evil and bring prosperity. Many join the festival from the neighboring Indian state of Bihar, where animal sacrifices have been banned in some areas.
Critics say the killings — carried out by slitting the animals' throats with swords — are barbaric and conducted in a cruel manner.
"We were unable to stop the animal sacrifices this year, but we will continue our campaign to stop killings during this festival," said Pramada Shah of the Animals Nepal group.
Government minister Saroj Yadav said he believed the festival was the biggest animal sacrifice in the world. "We haven't heard a bigger number. ... We are certain this is the largest one," Yadav said.
The slaughtered animals are taken back by devotees to their villages and eaten during a feast. The meat is considered blessed and consuming it protects them from evil.
The Associated Press and Sky News contributed to this report.