Several people had taken shelter under a tree when they were caught during heavy rains while returning from a football match last evening in Udharbond area, about 12-km from here.
The dead have been identified as 21-year old Rezaul Haque Barbhuiya, 17-year old Maidul Islam Barbhuiya) and 10-year-old Tahir Ahmed, police said.
The injured were admitted to a local hospital and some them were discharged after first aid, officials said.