West Bengal Chief Minister Mamata Banerjee
Hundreds of priests, school girls and other protesters staged a rally in Kolkata to support an elderly nun who was gang-raped at her convent school over the weekend.
Nuns dressed in white habits joined other women of all backgrounds and ages, including girls still in their uniforms, to express their sorrow over the attack and anger over incessant levels of sexual assault in India.
"We are not violent, we are not witches. And we will launch a big protest if attacks on Christian minorities continue," Kolkata businesswoman Hari Joseph Marien told news agency AFP.
Chief Minister Mamata Banerjee visited the nun, who is in her 70s and recovering in hospital, and said, "Some people have been arrested. Attempts are on to catch the mastermind." 10 men have been detained for questioning but no arrests have been made, even though the faces of four of the robbers were captured on CCTV footage.
"We are monitoring the borders. If they have run off to some other states, arrangements will be made to catch them," Ms Banerjee added.
The nun was attacked on Saturday after robbers ransacked the Convent of Jesus and Mary at Ranaghat, 70 kilometres (45 miles) from Kolkata, and stole cash and other items.
A holy scripture was also torn and a statue of Jesus was broken.
Prime Minister Narendra Modi in February pledged a crackdown on religious violence and freedom of worship for all faiths in the wake of the vandalism and arson attacks on churches, some of them in Delhi.
His government again came under criticism on Monday, with opposition lawmakers raising the nun's rape in the national parliament.
"Our PM has been saying again and again that he will ensure there is no attack on minorities. What is the sanctity of such assurances then?" asked D. Raja, a member of the Communist Party of India.