According to a senior official of the ministry, the survey found that on an average three lakh Bangladeshi infiltrators enter India annually and according to a rough estimate, the total number of illegal Bangladeshis in India is between 1.2 crore to 1.5 crore. The source said after 1971, about 15 to 20 lakh Bangladeshis had entered illegally in Assam. 1971 was the cut -off year as per the Assam accord although influx was greater before the Bangladesh War.

``Bangladeshis in Assam are in a position to influence the outcome of an election forcing all political parties to maintain a Bangladeshi appeasement policy in the state,'' he said. Bangladeshis have swamped three districts of Cachar and three Lower Assam districts where they are on the verge of becoming a majority.

The source admitted that although the ongoing barbed wire fencing has checkedinfiltration to some extent, it was still going on unabated as a large stretch of Meghalaya and Tripura remained unprotected by the fencing. The source said the survey was carried out considering the ground reports from all parts and in-depth analysis of the Bangladeshi census report and their demographic profile.

``Now even West Bengal has woken up after years of denying infiltration. They have rejected claims of 31.86 lakhs of suspected Bangladeshis in the rolls revision. Infiltration is the cause of grave concern not only to the eastern states but also for the country because Bangladeshis are migrating to all parts of the country,'' he said.

BSF's role in protecting the boundary has come under suspicion as the Home Ministry has ordered an inquiry into the recent confession of four ISI agents that they bribed the BSF to enter India.