Assam Violence
Villagers with their belongings move to relief camps as they leave their locality after violence at Chirang district in Assamreuters

From his hiding place in a cowshed, Sefaqul Islam watched as masked gunmen moved through his village, shot women and children dead with automatic rifles and tossed wounded survivors into the blazing remains of their homes.

The cattle herder's sister and seven-year-old nephew were among 41 Muslims killed by suspected tribal militants last week in Assam, the latest atrocity against people accused of being immigrants from neighbouring Bangladesh.

"We will never go back to the village," said Islam, as he and dozens of Narayanguri's traumatised inhabitants erected bamboo-framed tents on the opposite bank of the Beki river.

Police and local residents said three separate attacks were carried out by militants from the ethnic Bodo community as punishment for Muslims who failed to support their local candidate in the election, which is still going on across India.

The worst outbreak of communal violence in the northeastern region since 2012 has compounded fears among Muslims living along the India-Bangladesh border who feel they are being singled out by the man widely expected to be India's next prime minister - Narendra Modi.

The Hindu nationalist candidate, campaigning mainly on a ticket of economic growth, has ratcheted up rhetoric against illegal immigrants from Bangladesh, saying they should have their "bags packed" ready to be sent home should he win.

"The infiltrators have to go, go and go," Modi said on Wednesday in West Bengal, which also borders Bangladesh. "Don't you think they have made your life miserable?"

A few miles from Narayanguri, in an area prone to religious violence, Modi made a similar speech a few days before the massacres, warning that Bangladeshis were taking over the state.

While there is no evidence Modi's words had any bearing on the latest bloodshed in a long-running conflict, his rivals say the speeches, which continued after the attacks, risk alienating many in India's Muslim minority of 150 million people.

He has distinguished between economic immigrants from Bangladesh and Hindu refugees, whom he calls "family" escaping religious persecution in the Muslim-majority nation.

The prospect of an Indian prime minister forcing Muslims of Bangladeshi origin to return home has also raised alarm bells in Dhaka, where the government said it would resist any such move.

"If they do it, the relationship between the two countries will be jeopardized, it will be damaged," said Bangladesh Commerce Minister Tofail Ahmed.

"India, being a ... big country, a democratic country, a secular country, cannot take such a position."

MODI'S PARTY DEFENDS STANCE

Modi's Bharatiya Janata Party (BJP), which opinion polls suggest will lead the next government after a staggered, five-week election that ends on Monday, denies stirring tensions in Assam and has firmly condemned the killings.

Party leaders say it has every right to address what it says is an issue of national security, because immigration is part of a bid by Bangladesh to expand its borders informally.

"This is a fight between ethnic people and suspected foreigners who have captured our land and our jobs," said Ranjit Kumar Das, a BJP legislator in Assam's state assembly who lives in Barpeta Road, the closest town to the massacre.

"(The violence) is the natural outcome," he said. "If there is no permanent solution it will happen again and again."

The BJP also accuses the Congress party, which rules in Assam but looks set to be toppled from power on a national level, of failing to prevent the violence despite warning signs that trouble was brewing after voting took place there.

For its part, Congress says Modi is playing a divisive and dangerous political game in Assam, and the row has thrust a local issue on to the national stage during an election.

Reaction to Modi's speeches on social media shows people are listening. Posts under the #deportbangladeshis tag were at the top of Twitter's trend list in India on Monday.

"This should (send) shivers down the spines of illegal muslim immigrant pests, mostly thieves and dacoits (bandits)!" read one comment attached to an article about the killings.

For most of his tireless, 10-month election campaign, Modi, 63, has focussed on his credentials as an efficient manager capable of ending the worst economic slowdown in decades.

But he has failed to shake off doubts that he and his party are prejudiced against Muslims and will favour the Hindu majority at their expense.

Those date back to the party's rise in the 1990s following a mob's destruction of a mosque.

Modi has been accused of not doing enough to stop communal riots in 2002 in Gujarat, where he is chief minister, in which more than 1,000 people died, most of them Muslims.

He has repeatedly denied wrongdoing, and a Supreme Court inquiry found no case to answer.

"This violence has a long history," said BJP spokesman MJ Akbar, referring to the Assam attacks. "This knee-jerk reaction of blaming Narendra Modi for everything is absurd."

FENCE AND CAMERAS?

The situation on the ground is far more complex than Bodo against Muslim immigrants, BJP against Congress.

During this election, the BJP has tried to make inroads in the east of India where its support has traditionally been weak.

As part of the strategy, it has launched verbal attacks on leaders of Assam and West Bengal, accusing them of caring more for illegal immigrants than jobless youth from their own states.

Many local people in Assam, where the Muslim population has risen over the past century and now makes up some 30 percent of the population, agree with Modi. Nationwide Muslims account for around 13 percent of the population.

"Narendra Modi has boldly said what other politicians have not dared to utter so far," said Golap Saikia, a businessman in Assam's largest city, Guwahati. "Let us see how far he can achieve his commitment."

But even if Modi wants to deport illegal immigrants, identifying them would be a major problem.

Estimates suggest several million Bangladeshis and their descendents born in India have settled in the country over the decades, and a chief complaint of the BJP is that Congress gives immigrants voting papers.

Any push for mass deportation risks creating social unrest and leaving many of Assam's Muslims in limbo, since Bangladesh is unlikely to take them back - a situation with parallels to the plight of stateless Muslim Rohingya in Myanmar.

The relatively large Muslim populations in eastern India is partly explained by events in 1971, when East Pakistan became independent Bangladesh after a war that triggered a wave of migration into Assam and other states.

Better job prospects in India have continued to lure people over the border.

The BJP may look to strengthen the 3,909 km (2,429 mile) frontier by completing a fence running along it and adding security cameras, said Kanchan Gupta, a member of the BJP's national executive who worked on the party's election manifesto.