Indian and Bangladeshi border troops are on high alert after the two sides failed to resolve a row over hundreds of Bengali-speaking Muslims.
Both countries accuse each other of trying to force about 200 people at the centre of the row over their respective border.
Fears are growing for the well-being of the group, most of them snake charmers and their children.
They face their fourth night in make-shift tents, trapped in no-man’s land between the towns of Lalmonirhat and Cochbihar on either side of the border.
Many are said to be falling ill in the cold, wet conditions.
Dhaka says Delhi is in breach of international law and has wrongly identified them as illegal immigrants.
India has told local officials to prepare to evacuate villagers along the frontier after talks failed to resolve the dispute on Monday.
“Residents of Satgachi and its nearby areas are likely to be evacuated in view of the high tension along the border,” one senior Calcutta police official, NC Ghosh, told the Associated Press.
Indian officials have denied reports that border guards exchanged fire on Monday.
They told the BBC that no such incident had taken place.
In other reported trouble, Bangladesh’s state-run news agency said at least 30 people were injured when Indian and Bangladeshi civilians clashed along the frontier.
Delhi says the two countries have an agreement that, if people are detained while crossing the border on both sides, the country to which they belong should immediately accept them.
Bangladesh says in the past month, India has tried to force more than 2,000 Bengali-speakers across the border and that the overwhelming majority of them are Muslims from the Indian state of West Bengal.
But an Indian Foreign Ministry spokesman said they had documentary evidence the disputed people were Bangladeshi citizens.
Relations between India and Bangladesh have historically been good, but they worsened recently after Delhi ordered a crackdown on Bangladeshi immigrants.
India says up to 20 million Bangladeshis are in the country illegally. Dhaka says there are no Bangladeshis living illegally in India.
Meanwhile, those at the centre of the row are facing an increasingly dire situation.
India’s astounding ability to develop friendships with its neighbours becoming evident again…