Hindu nationalist Narendra Modi, the prime ministerial front runner in India's general election, has reiterated his strong stance against illegal immigrants, just days after a wave of sectarian killings in the northeastern state of Assam.
India is in the home stretch of a five-week election, which has heightened ethnic and religious tensions in many parts of the country.
Modi's opposition Bharatiya Janata Party (BJP) looks set to emerge as the biggest group.
India deployed troops in Assam on Saturday after more than 30 Muslims were gunned down in three days of what police said were attacks by Bodo tribal militants, who resent the presence of settlers they claim are illegal immigrants from Bangladesh.
Modi has repeatedly called for tighter border controls and said last week that illegal immigrants from Bangladesh living in the state of West Bengal should have their "bags packed" in case he came to power.
At a rally on Sunday, he accused the West Bengal state government of being soft on illegal immigrants because it was looking to secure votes from ethnic and religious minorities.
"You are concerned about infiltrators and not your own people ... they must go back, they are robbing the youths of India of their livelihood," Modi told the rally in the state, which borders Assam. Police said on Sunday that the death toll from the Assam attacks stood at 34 after they found the bodies of two 30-year-old women floating in the Beki river near Narayanguri village, where the worst of the attacks took place. A man's body was found elsewhere in the same district. All victims were Muslims.
Fifteen people had been arrested in connection with the attacks, including 10 forest guards employed by the state government and five former militants, police said.
Bodo tribesmen have long argued many of the Muslims in their part of Assam state are illegal immigrants encroaching on ancestral lands.
In 2012, clashes erupted in which dozens of people were killed and 400,000 fled their homes.
On Saturday, Prime Minister Manmohan Singh, of the ruling Congress party, condemned the latest attacks in Assam. Law Minister Kapil Sibal accused Modi of making divisive comments.
But BJP spokesman MJ Akbar said: "This violence has a long history. This knee-jerk reaction of blaming Narendra Modi for everything is absurd."
Voting in India's election, the world's largest ever democratic exercise, concludes next Monday and results are due on May 16.
Opinion polls have forecast the BJP will emerge with the biggest share of the 543 parliamentary seats, although the party could fall short of a majority.