Schools and colleges were closed from Apr 21 to Apr 27 due to the scorching heat throughout the country
They are receiving treatment at the Sheikh Hasina National Institute of Burn and Plastic Surgery in Dhaka, said Abdullah Al Arefin, deputy assistant director of the district Fire Service and Civil Defense.
The victims have been identified as Manik Mia, 32, and Md Ujjal, 35.
The guards went into a room on the seventh floor of the building around Sunday midnight to smoke, said locals. An explosion occurred immediately after they lit a fire.
Fire service personnel went to the spot and rescued them upon receiving the news.
Gas had accumulated in the room following a pipe leak which led to the explosion, fire service officer Arefin said.