The 17-year-old boy left his home in a small north Indian town on Thursday morning after telling his grandfather he was going to school. Instead he turned up 80km away in New Delhi, where he pulled out a gun and shot an anti-government protester.
The incident, captured in dramatic pictures on Thursday, was the first time a civilian had opened fire on protesters in the capital, raising fears that more Indians would take the law into their own hands as sometimes deadly protests rock the country.
A new law brought in by the Hindu nationalist government that fast-tracks Indian citizenship for non-Muslim minorities from three neighbouring countries has divided opinion, with the Hindu majority and Muslim minority often taking opposing sides.
Family members, neighbours, and a school official in Jewar described the boy - who cannot be named under Indian law because he is under 18 - as quiet and ordinary. His act of violence took them by surprise.
In social media posts and conversations with some classmates, he spoke of restoring Hindu pride and expressed admiration for a right-wing activist whom police have accused of fomenting violence.
"He wanted to do things for Hindus, he had that in his heart," classmate Shivam told Reuters, giving only his first name. "For years, he had said he was going to do something big."
Reuters has not been able to establish how the boy planned the attack outside Delhi's Jamia Millia Islamia University (JMU) or how he acquired the rudimentary gun. He fired a single shot, wounding a protester in the hand.
WhatsApp messages with another classmate, seen by Reuters, show that he asked for several thousand rupees three days before the shooting incident, without revealing why.
Since December, when the citizenship law was passed, hundreds of thousands of people have taken to the streets, saying the legislation is anti-Muslim and against the spirit of India's secular constitution. At least 25 people have been killed in clashes with police.
Prime Minister Narendra Modi's government says the law is designed to help persecuted minorities from Afghanistan, Bangladesh and Pakistan.
