The accident happened when the crackers were being destroyed by a committee formed by a mosque at Lisari Gate yesterday, said Ranvijay Singh, Station-in-charge, Lisari Gate police station.
The mosque had decided to do away with the tradition of cracker busting as it led to brawls in the area, he said.
The injured have been identified as Altamas (10), Mohammad Danish (9), Shoaib Khan, Naved and Mubussir. They were admitted to nearby nursing home, police said.
The incident is being investigated although no complaint has been registered in this regard, they added.