The incident took place when Bhanwar, 35, tried to unseal the bomb with his mouth without realising that it was an explosive. He was injured and rushed to the nearby hospital, the police said.
The bomb was received by the shopkeeper along with scrap sold by two women ragpickers, the police said adding both the women were detained for further interrogation.
Another crude bomb was found at the garbage bin but was defused immediately. Top police officials have reached the blast site for further investigation.
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