New Delhi, Dec. 11 -- The Opposition's main agenda is to keep undocumented migrants in the voter list but the government will fulfil its constitutional duty to "detect, delete and deport" them, Union home minister Amit Shah said on Wednesday, adding that the Congress lost elections not because of vote theft but poor leadership. In the Lok Sabha, a combative Shah said the Opposition was spreading one-sided lies about the special intensive revision for the last four months in an attempt to mislead the people, and asked why the Opposition was contesting elections if it believed the voter rolls were manipulated. The speech also saw a brief face-off between an angry home minister and leader of the opposition in the Lok Sabha Rahul Gandhi, and a walkout by the Opposition later. Prime Minister Narendra Modi lauded Shah's speech, saying he exposed the Opposition's lies about the election process. Replying to the debate on electoral reforms, Shah launched a frontal attack on the Opposition and said, "Their main agenda is to keep illegal immigrants in the voter list." As many Opposition parties walked out, the minister added, "Even if they walk out 200 times, we will not allow even one illegal immigrant in the country. Our policy is to detect, delete (from electoral lists) and deport. We will complete the constitutional duty." "Their (Opposition's) policy is to normalise intruders, and add names in the electoral roll to formalise them. It is my party's policy and I also believe that such a major demographic change is a danger to the country. This country has been divided on the basis of population in the past. We don't want our future generation to face another partition," the home minister added. The minister also linked illegal intrusion with the safety of democracy in India. "Can a country's democracy remain safe if illegal migrants decide who would be the PM and the CM? This SIR is nothing else but cleaning up of the voter list. I can understand some parties have political problems due to SIR. I feel sorry for them. Indians did not vote for them. Those foreigners who voted, now they will be deleted from the list. We have to decide whether foreigners will have voting rights to form Parliament and state assemblies. My opinion is, this cannot happen," Shah said....