Sailkumari, the wife of Rajdev Dixit, one of the deceased, had not attached the new LPG cylinder to the regulator-pipe which resulted in leakage, according to the police.
When she tried to light the gas-stove, it led to the blast.
Sailkumari suffered 90 per cent burn injuries and was being treated at government-run Kasturba Hospital. Her husband Rajdev, his brother Kapil Dixit (40) and Rajdev's sons Yashwant (17) and Jeetendra (20) were declared dead upon arrival at VN Desai Hospital.
Two other members of the family, Meera Upadhyay (40) and Shobha Dixit (35), suffered minor injuries.
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