Hindus are set to stage a vigil on boxing day to protest over the killing of an ailing temple cow.

Demonstrators will bang cymbals and drums outside the RSPCA's headquarters in Horsham, West Sussex, and hold a traditional Hindu ceremony for Gangotri, who was slaughtered at the Bhaktivedanta Manor temple complex, near Watford, while worshippers were at prayer.

The religious community's priests claim the RSPCA used "deceitful" tactics in destroying the animal and that the charity's actions amounted to religious sacrilege as it was killed on temple grounds.

However the RSPCA insisted it had acted in the animal's best interests and that it had not been slaughtered in secret and that temple staff were fully aware of what was happening.

The charity said the 13-year-old Belgian Blue-Jersey cross had infected sores, wasted limbs and breathing difficulties and three vets had agreed she was suffering and should be put down immediately.

The priests, who are also holding a simultaneous prayer vigil at the Bhaktivedanta Manor temple, say the ceremony is being held to mark the end of a traditional 13-day mourning period.

Gauri Das, the head of Bhaktivedanta Manor, said: "The community's Christmas has been overshadowed by this terrible event.

"It was a tragedy for thousands of our members, and especially the children."