The fire incident occurred in Super Gas Pvt. Ltd was reported at around 6:30 am and was doused after nine hours, the police informed.
The reason behind the fire is still uncertain. Local authorities have suspected that the fire caused due to leakage of gas when it was being unloaded from the tanker.
The deceased victims Madhusudan Mishra and Yadav Prasad Adhikari have been confirmed dead after they were reported to be missing earlier. Three other firefighters, along with three locals, have sustained severe injuries.
Chief District Officer Binod Prakash Singh said, "Our firefighters were later joined by firefighters from India, which helped us to control the fire soon."
The investigation on the fire incident is underway. The injured have been airlifted to Kathmandu for further treatment. (ANI)