Hindu monks clad in saffron robes served legal papers on Britain's leading animal welfare charity on Friday in protest at the slaughter of one of their sacred cows.
"Mother Gangotri," a 13-year-old Belgian Blue-Jersey cross, was put down by the RSPCA (Royal Society for the Protection of Cruelty to Animals) on December 13 last year in what the charity called a mercy killing.
But monks and nuns of Bhaktivedanta Manor, Europe's biggest Hindu temple in Hertfordshire, north of London claim it was illegally slaughtered while they were at worship.
And on Friday six of the monks marched on the RSPCA's headquarters in Horsham in West Sussex, south of London.
"The RSPCA unlawfully trespassed on temple property and unlawfully trespassed on the life of a cow," said Gauri Das, president at Bhaktivedanta Manor.
"The cow was under veterinary care and was recovering. There was absolutely no reason for her to be killed. The way they carried out this act on the sacred premises of a temple with no dialogue was completely unacceptable."
The campaign, called Justice for Gangotri, also cites the case of Shambo, a bullock put down at a Hindu community in west Wales last year after a positive test for bovine tuberculosis.
His demise caused outrage among Britain's 750,000-strong Hindu community -- Britain's third-largest religion after Christianity and Islam -- who regard all life as sacred.
In January, around 100 protesters gathered outside the House of Commons to protest over the RSPCA's actions.
Bhaktivedanta Manor runs the Cow Protection Project, which cares for old cows and bulls, and allows them to die naturally.
The RSPCA denies the claims, saying it informed staff at the temple of what they were going to do, and avoided killing the cow during prayers.
"We believe we acted properly, within the law, but clearly they are of a different opinion," said John Rolls, RSPCA director of animal welfare promotion.
"I am sorry it has got to this point. I think the issue could be addressed through dialogue rather than the courts and it is unfortunate they are taking this action."