Indian police fired blanks on Thursday as thousands of protesters ignored a curfew in the north-east of the country, in a fresh day of demonstrations against contentious new citizenship legislation.
Officials said 20-30 people have been hurt in the protests in recent days, with vehicles torched and police firing tear gas and charging the crowds with heavy wooden sticks.
Five thousand paramilitary forces were deployed in the city of Guwahati in Assam state, while many roads and highways were blocked to prevent the spread of protests.
All train services to Tripura and Assam were suspended and some flights were cancelled. Several cricket and football matches scheduled to take place in Assam were cancelled amid the curfew.
Prime Minister Narendra Modi sought to calm the situation in a series of tweets that many in the region could not read because mobile internet was blocked in some areas.
The Citizenship Amendment Bill, passed by the upper house on Wednesday, allows for the fast-tracking of citizenship applications from religious minorities from three neighbouring countries, but not Muslims.
For Islamic groups, the opposition, rights groups and others, this is part of Modi's Hindu-nationalist agenda to marginalise India's 200 million Muslims, something he denies.
Many in India's far-flung north-east object because they fear that the legislation, which prompted angry exchanges in parliament this week, will give citizenship to Hindu immigrants from Bangladesh.
"I want to assure my brothers and sisters of Assam that they have nothing to worry after the passing of #CAB (Citizenship Amendment Bill)," Modi tweeted, referring to the biggest state in the north-east.
It is not yet clear if the legislation, after being signed off by the president, would survive a constitutional challenge in the Supreme Court.
The Indian Union Muslim League filed a petition in the top court, the first challenge against the bill, with the political party's leader saying it was against the basic principles of the country's constitution.
"The constitution says there will be no differentiation based on caste, religion or anything. Here, the citizenship is being given on the basis of religion," P.K. Kunhalikutty told AFP.
"The CAB... won't stand in front of the law."
The petition states that the they "do not have any grievances in granting citizenship to migrants but the petitioners grievances is directed against discrimination and unreasonable classification based on religion."