The three along with five others suffered burn injuries in the blast occurred around 11:45 am on Saturday in the warehouse, said officer-in-charge of Turag Police Station Mehedi Hasan.
Local people rescued them and rushed to the emergency department of Sheikh Hasina National Burn and Plastic Surgery Institute.
The other injured, Md Mizan, 35, Masum, 35, Md. Al-Amin, 30, Shafiqul and Md. Shaheen, 25, are undergoing treatment at the hospital with severe injuries.
Among them, Mizan and Masum received 95 per cent burn injuries while Shafiqul received 80 per cent, Al-Amin 75 per cent and Shahin received 35 per cent, SM Ayub Hossain added.