The Animals Asia Foundation has called on Vietnamese authorities to end a pig slaughter festival which it says is "extremely cruel", but some scholars argue that any community should be left to decide their own customs.

On Tuesday, the advocacy group launched an online petition, asking people to join and oppose the festival, which is part of the tradition Lunar New Year celebrations at Nem Thuong Village in the northern province of Bac Ninh Province.

The Hong Kong-based group, which has been very active in protecting bears in Vietnam from the bile extraction industry, has also sent statements to the culture and tourism ministry and Bac Ninh government, asking them to ban the festival.

During the festival, villagers will parade two pigs amid loud drums and trumpets, which the group said “only make them more stressed and panic before being killed.”

Then some villagers will slit the pigs' throats, while their legs are still tied in ropes, to take the blood for luck, local media described.

Villagers believe the pigs’ blood represents luck and prosperity. They will wet money notes with the blood and place them on the altars in their houses.

Locals said they hold the festival on the sixth day of the first lunar year -- February 24 this year -- to commemorate Ly Doan Thuong, a general who was fighting Chinese invaders nearly a thousand years ago.

One time he and his soldiers took refuge at the village, then still a wild jungle area.

They ran out of food while there were many wild hogs in the area, so he decided to let his soldiers hunt some to eat.

Animal protection or cultural imperialism?

Animals Asia said in a post on its website that the practice is “completely inappropriate for a dynamic and modern country like Vietnam.”

But some Vietnamese social and cultural researchers say the group has been insensitive with their statements.

Its animals rights campaign might be violating the cultural freedom of the village, they argue.

Professor Ngo Duc Thinh, who once headed the Vietnam Institute of Culture and Arts Studies, said nobody has the right to judge others’ culture as barbaric.

The principle is that all customs and traditions are equal as long as they do not violate human rights, Thinh said, as cited by The Thao & Van Hoa newspaper.

Forcing the villagers to stop practicing the tradition is impossible and something we shouldn’t do" -- Nguyen Van Phong, head of the province's culture department

Historian Duong Trung Quoc told the paper he would support Animals Asia’s petition if it is just about animals rights.

But the matter is about a spiritual tradition and “we should show some good will to learn about its history.”

Quoc said the group can make a suggestion.

“But any changes to the festival should be made by the local community by choice.”

Professor Tran Lam Bien, a culture and religion researcher, said that local experts have debated often about whether the festival should be changed, but they agreed to let the villagers decide.

He said the festival is spiritual at its root. The villagers want to offer the pigs’ blood to the village’s gods to pray for good crops and health.

But its increasing popularity has made it look bad, he conceded.

“Many strangers curious about the festival have come and watched the killing as something joyful.”

Nguyen Tu Quynh, vice chairman of the province, said they actually have been open to international criticism and tried to adjust the practice.

Quynh told news website Dan Tri that the government issued a statement in February 2013 encouraging locals to scale down the festival and to parade the pigs only without killing them.

Nguyen Van Phong, director of Bac Ninh’s culture department, said the villagers last year agreed to keep the slaugher inside a tent with the village’ leaders and a few families, instead of doing it in front of a large audience.

He said the villagers used to cut the pigs in half at the belly, but now they only drew blood.

“Forcing the villagers to stop practicing the tradition is impossible and something we shouldn’t do,” he concluded.