The Prime Minister says, terrorism and Left-wing extremism are two major challenges to society. Addressing the National Integration Council meeting in New Delhi on Saturday, Dr Manmohan Singh said the Delhi High Court blast is a stark reminder that there cannot be any let up in the security set up. He said no civilised society can tolerate loss of innocent lives in the pursuit of any ideology. Dr Singh said there is a need to identify and address causes of radicalisation of our youth. He said, the government is making special efforts for development of backward areas, which are affected by Left wing extremism. The Prime Minister said the investigating agencies should free from bias and prejudices of any kind. Dr Singh said there is a need for continuously upgrading and strengthening the investigating agencies and intelligence gathering apparatus to deal with the newer methods and technologies that the terrorists and naxals adopt. The Prime Minister said, the active interest displayed recently by the people in the national debate on corruption augurs well for the future of the country. On the development front, Dr Singh said, the government has taken several steps to ensure higher growth, coupled with greater inclusion. Speaking on the occasion, the Home minister Mr. P Chidambaram said, use of violence as an instrument of protest or an instrument of change is biggest challenge before country.