Kolkata, March 15 (IANS): Promising strict action, West Bengal Governor K.N. Tripathi on Sunday sought public help to arrest those who gang-raped a 70-year-old nun in Nadia district.

In an incident that had caused revulsion in the state and beyond, the nun was brutalized by a gang of bandits inside the Convent of Jesus and Mary in Ranaghat, some 80 km from Kolkata, early Saturday.

"The state government will take strict action in this matter," Tripathi told the media.

"The administration will surely apprehend the culprits and punish them. I feel the people should also come forward to help nab the culprits," he said.

Police have published snapshots of four of the culprits obtained from CCTV footage and announced a reward of Rs.1 lakh for any information about them.

Five people have been detained for questioning.

Chief Minister Mamata Banerjee on Saturday ordered the Criminal Investigation Department (CID) to probe the matter and promised "swift" and "strongest action" against the culprits.

State Commission for Women chairperson Sunanda Mukherjee on Sunday morning reached the convent and talked to the school authorities and other members.