Kolkata/New Delhi, Mar 7 : Bharatiya Janata Party (BJP) has blamed the Central Government for what they termed as a failure to check flow of illegal migrants from Bangladesh.

Addressing a election rally in Kolkata, BJP prime ministerial candidate L. K. Advani said, "Hundreds of thousands of illegal immigrants enter West Bengal from Bangladesh and even the Supreme Court has said that what is happening in the eastern part is nothing less than external aggression and because this government abolished laws that deftly handle it, all this is getting encouraged."

New Delhi estimates there are up to 20 million illegal Bangladeshi immigrants in India -- mostly poor people who come in search of jobs. Issue of illegal migrants usually hogs limelight as elections near, with rival political formations blaming each other of trying to appease the immigrants for votes.

The Congress on the other hand passed the blame on to the BJP saying lack of enough recruitment of security personnel during their regime had led to the current situation.

"What you have done and failed to do has an cascading effect and today we have to recruit in large number to make up that backlog. One consultant has also been appointed. You (BJP) have played with the security of the country, you have been negligent and you owe an answer to the people of this country of what you have done for the security of the country except just criticising us (Congress) in the parliament," Congress spokesman Abhishek Manu Singhvi told reporters in New Delhi.

The political horizon was abuzz with activity as more and more outfits wooed smaller groups and political heavyweights to bolster their poll prospects.

Ajoy Pratap Singh, son of former Prime Minister Viswanath Pratap Singh joined Lok Janshakti Party led by Ram Vilas Paswan.

Paswan appealed to the other constituents of the ruling United Progressive Alliance not to field any candidate against Ajoy Pratap Singh.

Ajoy Pratap said his mission was to fulfil the wishes of his father.

"I will work with the Lok Jana Shakti party and will carry forward all the works begun by my father in sectors like social justice, poor and farmers," he said.

The Communists, who have joined a Third Front as an alternative to the UPAe and the opposition National Democratic Alliance, said they would shift in foreign policy if voted to power.

"The focus of the country according to us needs a new policy direction and this policy direction requires both to strengthen India''s secular democratic character against the assault by communal fundamentalist and terrorist forces. It is require to user in a new thrust in the economic policies which are people centric and to make India pursue an independent foreign policy and not been any appendage to any major power in the world On these issues we think there is a need for policy shift and that policy shift can come about only by a combination of secular forces who are who are anti-Congress and anti-BJP," said Sitaram Yechury, politburo member of Communist Party of India- Marxist.

India will hold the elections between April 16 and May 13, a mammoth process in which 714 million people will be able to cast their votes.

Counting of ballots would take place on May 16. (ANI)