Elderly nun raped in Indian convent school
The group vandalised the school and then one of them attacked the nun, local police officer Abhijit Biswas said, adding that the victim was in hospital and no one had so far been arrested.
Chief Minister Mamata Banerjee of West Bengal state, where the school is located, condemned the incident and said "swift, strongest action" would be taken.
The death of a student after a brutal rape in New Delhi in 2012 caused national outrage and raised public pressure for faster justice in a country where crime against women is rampant but court cases can drag on for years.
Days ago a mob of several thousand people broke into a high-security prison in northeastern India, dragged out a rape suspect and killed him in full public view.
(Reporting by Krishna N. Das and Sujoy Dhar; Editing by Mark Trevelyan)