"It is due to the careless attitude of the school

of the school, identified as Sushil Kumar Sharma, and subsequently, he has been arrested. The class XII student, who threw the javelin which hit the boy, has also been identified, police said.

The school principal, Niranjan Lal Sharma, has been asked to join the police investigation.

The victim lives along with his father and elder brother, Rakesh (17), who is a class XII student in a separate government school in Saket. His morther, Shanti, died two years ago. The trio live in Chirag Dilli area along with their uncle and aunt.