The deceased, Vipin Kumar, 15, took objection to a 16-year-old local youth whistling at him in a mocking fashion which led to the row, the police said. In a fit of rage, the accused landed a punch on Vipin’s head. The boy fell on the concrete pavement, head first, his friend told the police.

Death came almost instantly, said doctors at Guru Gobind Singh Hospital, where Vipin’s father rushed him.

The incident occurred on Tuesday evening at Raghubir Nagar market.

The police today arrested the accused; he will be produced at the juvenile court on Thursday.

Vipin’s uncle Bhagwan Das said: “He had gone to the market around 8 pm with his friend, Mani. We were a little anxious to see Mani return in a cycle rickshaw within half-an-hour. But then we saw Vipin’s body next to him on the rickshaw.”

He was dead by then, as per the medical report at the hospital.

The boy’s maternal uncle, Ajay Kumar, told Newsline that Vipin worked at a garment shop in Rajouri Garden market. “He had gone to the market last evening to buy some new clothes for Shivratri,” Kumar said.

The MLC report at Guru Gobind Singh Hospital suggests a needle-like puncture on the back of Vipin’s head caused death. Significantly, the report quotes Vipin’s father Naresh telling doctors that the boy died as a result of a fall while playing.

But, his relative Ajay Kumar said, “Naresh did not know the sequence of events at the time. His first priority was to rush his son to the hospital.”

The police have registered a case of culpable homicide not amounting to murder (Section 304 of Indian Penal Code) against the accused. “The act was not premeditated, as suggested by the MLC report,” a senior police officer said. “We have taken down Mani’s statement.”