Mumbai: Opposition Congress and NCP today demanded immediate ban on Sanatan Sanstha after its members came under scanner in Govind Pansare murder case, with the NCP also blaming former Union Home Secretary R K Singh for not banning the ultraconservative organisation.

NCP spokesperson Nawab Malik said the request of the previous (Congress-NCP) government in Maharashtra to ban the outfit was not heeded by the Union Home Ministry because of bureaucrats like R K Singh who were "soft" on such organisations. Singh is now a BJP MP in the Lok Sabha.

"UPA government is criticised for not accepting the state government's request to ban Sanatan. But if people like Singh sit on the file, the decision cannot be taken," Malik alleged.

In 2011, after getting information about the organisation's activities, Congress-NCP government had recommended that the outfit be banned. "However, R K Singh, who was close to BJP, was the Union Home Secretary and he delayed the decision," Malik added.

Leader of Opposition in the Legislative Assembly and Congress leader Radhakrishna Vikhe-Patil demanded the arrest of Sanatan Sanstha leaders and ban on the organisation for threatening journalists.

State Congress spokesperson Sachin Sawant condemned Shiv Sena for supporting Sanatan. "Eliminating those who oppose your political ideology is also an act of terrorism," he said.

Sameer Gaikwad, a member of Sanatan Sanstha, was arrested last week in connection with the murder of CPI leader Govind Pansare. Senior journalist Nikhil Wagle too had reportedly got threats from the Sanstha.