Several thousand people stormed a prison in north-eastern India, where they dragged away a man accused of rape and then lynched him.
The mob overpowered security at Dimapur Central Prison in Nagaland and seized the rape suspect, whom they also accused of being an illegal migrant from Bangladesh.
They pelted him with stones and beat him to death, said police constable Sunep Aier.
The man had been arrested on suspicion of raping a local woman on February 24.
In recent years, India has seen an outpouring of anger against sexual violence that is pervasive across the country.
But the killing was also probably linked to tensions in Nagaland over an influx of migrants from Bangladesh. Dimapur, the largest city in Nagaland, is 1,660 kilometres (1,000 miles) east of New Delhi.
Several local groups accuse the migrants of taking away their land and jobs and have been protesting in recent weeks.
Amnesty International said members of a mob who lynched the man must be brought to justice.
Shemeer Babu, Amnesty India’s Programmes Director, said: “The Nagaland government, which is probing this gruesome incident, must ensure that every person who was part of the mob is brought to justice.
“Failure to do so will send the message that anyone can commit outrageous abuses and attempt to justify them as an expression of public anger.
“Nagaland authorities must uphold the rule of law. Violence against women needs to be tackled with swift and effective responses from the state, not with barbarism by self-appointed vigilantes.”
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