The explosion in a building at Dhaka's Science lab area was a massive accident, said Fire Service and Civil Defence Director General Brig Gen Md Moin Uddin on Monday.
"We are primarily suspecting that accumulated gas caused the blast. We are investigating further and looking into other probabilities," he said while talking to reporters after attending an event at Mirpur DOHS, reports UNB.
He also said that the army's bomb disposal unit found no sign of explosive substances on the spot.
At least three people died and more than 50 were injured when Shirin Mansion, a three-storey building, partially collapsed due to an "explosion that triggered a fire" at Dhaka's Science Lab area on Sunday.
The deceased were identified as Tushar, Shafikuzzaman, and Abdul Mannan.
A team comprising members of the bomb disposal unit and chemical disaster response team (CDRT) of Bangladesh Army inspected the explosion site Sunday afternoon and carried out tests.
On Sunday afternoon, the Dhaka South City Corporation (DSCC) authorities put up a banner declaring the building dangerous and abandoned.
