By Nick Caistor
In Port-au-Prince, Haiti
The drumming and chanting goes on hour after hour. A goat and a small black pig have their throats cut, and the blood is sprinkled over the worshippers.
Voodoo is deeply rooted in this country of eight million people
The animals are thrown into a pool of brown, bubbling mud.
Many of the blue and red-robed believers jump into the pond as well.
This is the climax of the voodoo ceremony at the Plaine du Nord, some 300 kilometres north of the Haitian capital, Port-au-Prince.
Thousands of Haitian voodoo believers make the trek to the Plaine du Nord each year - some of them from as far afield as the United States and Canada.
"I come here because I have lots of problems," says Mironne, from nearby Cap Haitien. "The saints will help me, and it brings me and all my friends together."
This voodoo ceremony is in honour of Ogou, the spirit of fertility and the earth: but also of the Catholic saint of Saint James, the warrior saint, and is held every year towards the end of July.
Throughout the month of July there are voodoo ceremonies and pilgrimages all over Haiti.
But this year for the first time, voodoo has been recognised as an official religion in Haiti, where it has been practised for almost 300 years.
Some of the believers jump into the mud
"We have our own temples," Nene, a voodoo priest or houngan tells me. "We believe in God, and we baptise people, we have religious ceremonies, so of course we are a church."
This recognition of voodoo, which combines a belief in a single god with the worship of ancestral spirits that enter the body of its believers in ceremonies like the one at Plaine du Nord, does not please everyone.
"The Bible tells us we are made in the image of God," says the Catholic priest Adonais Jean-Juste. "But these people who bathe in mud are behaving like pigs - they're the animals who like to roll in mud. These voodoo believers need to be made clean by being baptised in Christ."
Others are more understanding.
"People who are possessed by voodoo spirits feel two things," says John Hoet, a Belgian priest who has spent all his adult life working in rural Haiti.
Thousands make the journey to Plaine du Nord every year
"Often for the first time in their lives they feel they are important. They speak with a voice of authority, the voice of Ogou, and people listen to them."
"They also feel part of a community, and protected in a way they are not protected by anyone else in their lives."
After the ceremony at the Plaine du Nord, the believers move on at dawn to bathe in the sea at nearby Limonade, with their faith renewed.
Despite the suspicions of other religions, and despite its reputation for black magic, voodoo is ever more deeply rooted in this Caribbean country of some eight million people.
As the Catholic missionary John Hoet admits: 'Haitians may be 95% Catholic, but they are 100% voodoo."