Readers may find images in this article distressing.
Hindu devotees in Nepal have begun slaughtering hundreds of thousands of animals and birds in a ritual sacrifice for the 'Gadhimai Mela' festival.
The ceremony, which takes place every five years, is believed by worshippers to appease the Hindu goddess of power, in turn bringing luck and prosperity.
It is thought to be the largest such animal sacrifice in the world and has long attracted criticism from animal rights activists.
"It is a ritual connected with people's faith," said Yogendra Dulal, an assistant administrator of the Bara district, near the border with India, where the temple is located. "We can't hurt their sentiments and ban the practice."
Tens of thousands of people attend the two-day ceremony, where around 500,000 animals are killed, according to estimates by Humane Society International.
Sacrifices begin at dawn when a rat, a goat, a rooster, a pig and a pigeon are killed.
Around 5,000 buffaloes are beheaded by butchers using swords and large curved knives.
The animal's heads are then buried in a huge pit, while the hides and skin are sold to traders.
India's Supreme Court recently asked the government to stop the illegal movement of animals into Nepal for the ceremony.