A seven-year-old boy was killed and another child injured in a crude bomb explosion in Burdwan city in West Bengal on Monday, police said. The incident happened around 11 am in Rasikpur's Subhaspally area of the city, they said. Sheikh Afroz (7) and Sheikh Ibrahim (9) were playing near their house when they hit a packet in which the crude bombs were kept, leading to the blast, Burdwan police station's inspector-in-charge Pintu Saha said.