The probe team said they could not prove beyond doubt whether electric shot-circuit or an act of sabotage was the cause of the fire. They, however, did not dismiss the possibilities of sabotage.

The five-member committee headed by Joint Secretary Mushtaque Hasan Mohammad Iftekhar submitted a 16-page report to the industries ministry yesterday.

In the report, it said the BSEC Bhaban was not built maintaining the building code and fire-extinguishing arrangement there was not adequate.

The fire originated at the first-floor office of the Bengal Group Ltd at around 10:00am, said a press release the industries ministry.

The probe team suspects that there were highly explosive substances somewhere on the first floor and fanned by those, flames swept through the building despite attempts to douse the fire, it added.

It all could be known once the chemical tests of the evidence are done, it added.

Meanwhile, a well-placed source said the committee thinks that chemical substances at a medical centre on the first floor and a gas burner at the BSEC office might have caused the fire to spread fast.

The probe also could not find out how the Dandy Dying on the eighth floor caught fire two hours later when the fire on the first and second floors was already contained.

The industries ministry said a complete assessment of the damage would take some more time.

The enquiry team has made a number of recommendations to stop repeat of such disaster. Those include having an alternative staircase, avoiding setting up stairs and lifts in the middle of a high-rise structure and ensuring the electric ducts are at a safe distance, said sources.

Asked to comment on their failure to pinpoint the cause, head of the probe team Mushtaque Hasan told The Daily Star: "We're no specialists in chemical tests. It's the job of the government experts and they are doing that now. We'll be able to know what set off the fire and why it spread so fast only after getting the test results."

He said his committee would give an exact cause of the blaze in a follow-up report to be submitted soon after the laboratory works.

Meantime, ntv that was on the eighth floor of the 11-storey office block has decided to back on air as a trial run-through from 6:00pm today.

They said they have hired the second and third floors of the UTC Building at Karwan Bazar to start the transmission initially for six hours.

The private TV channel will start 24-hour test transmission from the next Friday or, if failed, the next Monday, ntv Executive Director Hasnain Khorshed, told reporters at a city hotel yesterday afternoon.

It will go into full-scale transmission in 15 days.