Story highlights Official says men broke into a convent school and one sexually assaulted a septuagenarian nun

A series of publicized rapes have occurred in India in recent years

New Delhi (CNN) A gang of robbers struck a Christian school in eastern India on Saturday, and one of them raped a 71-year-old nun, a senior official said.

The man apparently did so, because she resisted the robbers, said P.B. Salim, chief administrator of the West Bengal state's Nadia district.

Previously, a church official had told CNN sister broadcaster CNN-IBN that three or four of the men had raped the woman.

A group of seven to eight men allegedly barged into the school and its attached staff residence during pre-dawn hours, and the elderly Sister Superior raised an alarm and resisted, Salim said. The rape was apparently punishment for it.

Later, the men tied her up along with two other nuns and the building guard. The robbers then made off with cash worth a few hundred thousand rupees (thousands of dollars), laptops and other articles, Salim said.

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