India deployed troops to the state of Assam on Saturday after 31 Muslims were gunned down in three days of what police said were attacks by tribal militants who resent the presence of immigrants from neighbouring Bangladesh.
The unrest in the tea-growing state comes towards the end of a marathon election across India that has heightened ethnic and religious divisions and which the Hindu nationalist Bharatiya Janata Party (BJP) looks set to win.
Security forces found the bodies of nine people with bullet wounds on Saturday, six of them women and children, the third day of violence that police have blamed on Bodo tribesmen attacking Muslim settlers as punishment for opposing their candidate in the election to the Indian parliament.
Bodo people are followers of the local Bathouist religion.
"We are scared to live in our village, unless security is provided by the government," said Anwar Islam, a Muslim who had come to buy food in Barama, a town about 30 km (20 miles) from the villages in the Baksa district where the violence erupted on Thursday and Friday.
He said men armed with rifles had come to his village, Masalpur, on bicycles and had then fired indiscriminately and set huts on fire.
Bodo representatives say many of the Muslims in Assam are illegal immigrants from Bangladesh who encroach on ancestral Bodo lands. In 2012, clashes erupted in which dozens of people were killed and 400,000 fled their homes.
In addition to that violence, Assam has a history of sectarian strife and armed groups fighting for greater autonomy or secession from India.
Election candidates, including the BJP's Narendra Modi, the front-runner for prime minister, have been calling for tighter border controls.
On Saturday, the ruling Congress party blamed Modi of using divisive rhetoric. "Modi is a model of dividing India," said Law Minister Kapil Sibal.
Modi said last week that illegal immigrants from Bangladesh in the nearby state of West Bengal should have their "bags packed" in case he came to power, accusing the state government of being too soft.
"Modi should have been more responsible in his utterances," said Sabyasachi Basu Roy Chowdhury, a political science professor at Rabindra Bharati University in Kolkata, the capital of West Bengal.
"His words can be very damaging since, even if we consider that Bangladeshis are living here illegally, there is a question of human rights too."
But the BJP said it was the responsibility of the Congress party that governs the state to ensure law and order and crack down on militants.
Soldiers in convoys of trucks mounted with rifles were patrolling on Saturday in Baksa district, where some of the attacks took place.
Bodies covered with white sheets were laid out in a row at a police outpost on the edge of Barama for identification by relatives.
Most Muslims were staying together in big groups, villagers visiting the market in Barama said. Security forces found three children hiding in forests near the border with China.
The Bodo region faces what residents say is a tight race between a Bodo and a non-tribal candidate. A policeman was killed during the voting when the region went to the polls on April 24.
"There's heightened tension because of the election," said Ajai Sahni, executive director of the Institute for Conflict Management in New Delhi, although he said it was too early to be certain about exactly what had provoked the attacks.
India's staggered voting concludes on May 12 and results are due to be announced on May 16.
Modi is tainted by accusations that he turned a blind eye to, or even encouraged, Hindu-Muslim riots in 2002 in Gujarat, the state he has governed for 13 years. More than 1,000 people, most of them Muslims, were killed.
He has always denied the accusations and a Supreme Court inquiry did not find evidence to prosecute him.
(Additional reporting by Sujay Dhar in Kolkata; Writing by Shyamantha Asokan and Sanjeev Miglani; Editing by Robin Pomeroy)