According to the police, the incident occurred on April 11 under Kairana police station when unknown persons opened fire at a house in Ramda village of neighbouring Shamli district and injured 11 family members including ten-year-old Nadeem.
The other members injured in the firing were identified as Mubarik, Furkan, Ishak, Gufran, Irshad, Shakir, Arif, Muntazer and Mehtab Shamshad.
The victims were rushed to a nearby health centre where Nadeem succumbed to his injuries, police said, adding the body was sent for postmortem.
Muzaffarnagar and neighbouring districts including Shamli in western Uttar Pradesh had witnessed communal riots in September last year that left over 60 people dead and thousands of people displaced. The 10 western UP districts had gone to polls on April 10.