Fire service chief Brigadier General Muhammad Jahed Kamal has said it is too early to tell whether Thursday's Secretariat fire was caused by sabotage or was an accident.
The director general of the agency made the statement on Friday after a government probe committee visited the scene.
The committee started its investigation into the cause of the fire at the Bangladesh Secretariat earlier.
Jahed said the investigation is ongoing, and nothing definitive can be said at this stage.
"It is too early to comment whether this fire was caused by sabotage or was an accident. We are here to observe the site. Further details will be provided based on the investigation."
On Thursday, the government disbanded its initial seven-member investigation committee and formed a new eight-member committee to investigate the fire at the Secretariat.
The new committee was formed with the senior secretary of the Ministry of Home Affairs as the chairman and the director general of the Fire Service and Civil Defence as the member secretary.