Protests against a divisive new citizenship law continued in north-east India on Saturday as Washington and London issued travel warnings for the region following days of violent clashes in which at least two people died.
Many in the north-east fear the new legislation will grant citizenship to large numbers of immigrants from neighbouring Bangladesh, whom they accuse of stealing jobs and diluting the region's cultural identity.
Several thousand protesters rallied in the Indian capital New Delhi late on Saturday to urge Prime Minister Narendra Modi's government to revoke the law, some holding signs reading: "Stop Dividing India".
"People are not gathered here as Hindus or Muslims. People are gathered here as citizens of India. We reject this bill that has been brought by the Modi government and we want that equal treatment as is enshrined in our constitution," said protester Amit Baruah, 55.
Protests turned violent in West Bengal state, a hotbed of political unrest, with at least 20 buses and parts of two railway stations set alight as demonstrators blocked roads and set fire to tyres. No injuries were reported.
Tensions also simmered in Guwahati in Assam state, the centre of the unrest. Medical staff said two people were shot dead and 26 taken to hospital late on Thursday after the security forces opened fire.
Assam police chief Bhaskar Jyoti Mahanta told the Press Trust of India late on Saturday that 85 people were arrested in connection with the protests, and that officials were working to identify violent demonstrators caught on video.
Friday's funeral procession of Sam Stafford, 18, who was killed in the protests, was attended by hundreds of angry and distraught mourners who shouted "long live Assam".
"We were watching news all day on TV about the protests when my nephew left home in the evening. We asked him not to go, but he went with his friends," the student's aunt, Julie Stafford, told AFP.
Anticipating further unrest, the authorities extended an internet ban across Assam until Monday.
Most shops were shut and anxious residents stocked up on supplies on Saturday when the curfew was relaxed during the day.
The Citizenship Amendment Act allows for the fast-tracking of applications from religious minorities including Hindus and Sikhs from Pakistan, Afghanistan and Bangladesh, but not Muslims.
Samujjal Bhattacharya from the All Assam Students' Union, which has been at the forefront of the protests, told AFP the group would continue its fight against the new law "in the streets and in the court".
Mr Modi and his Japanese counterpart Shinzo Abe postponed a summit that was reportedly due to be held in Guwahati from Sunday. The United States and Britain warned their citizens to "exercise caution" if travelling to the wider north-east region.
Islamic groups, the opposition and rights organisations say the law is a part of Mr Modi's Hindu nationalist agenda to marginalise India's 200 million Muslims.
He denies this and says that Muslims from the three countries are not covered by the legislation because they have no need of India's protection.
Mr Modi's right-hand man Amit Shah on Saturday sought to reassure the north-eastern states, saying the government would protect their "culture, social identity, language and political rights".
Assam has long been a hotbed of ethnic tensions. In 1983 about 2,000 people, mainly Bengali Muslims, were butchered in what became known as the Nellie massacre.
This year a citizenship registry left off 1.9 million people – many of them Muslims – who were unable to prove that they or their forebears were in Assam before 1971, leaving them facing possible statelessness.
"There has been this agitation [against] illegal migration from Bangladesh over many years," Sanjoy Hazarika, a professor at Delhi's Jamia Millia Islamia University, told AFP.
"They feel that their rights to land, to jobs, and the entire social fabric education, existing social services and so on will be impacted by this," he said.
On Friday, university students in Delhi clashed with police, who used batons and tear gas to quell the protests.
The passage of the bill also sparked angry scenes in both houses of parliament this week, with one legislator likening it to anti-Jewish legislation created by the Nazis in 1930s Germany.