Probe committees, formed to investigate the Naraynganj mosque explosion, are now looking into if the building had Titas Gas Transmission and Distribution Company Limited's permission.
An official involved with the investigation said this to The Business Standard.
"The negligence of Titas Gas led to the accident. There is no doubt about it. But it is crucial, for the investigation, to find out if the mosque committee informed the concerned authorities before setting up the building," a member of Narayanganj district administration probe committee told The Business Standard.
While visiting the spot on September 5, State Minister for Power, Energy and Mineral Resources Nasrul Hamid said the mosque may have been built on government land.
Also, the mosque has been said to be set up on a gas pipeline.
Baitus Salat Jame Masjid Committee President Abdul Gafur said they did not know a gas pipeline passed beneath the mosque while starting its construction.
"Last year, we saw that gas bubbles were coming out from a side of the mosque."
When asked, if they took permission of the concerned authorities for the building, Gafur said the work started in 2000. "So it is difficult to say what happened then."
However, none of the six air conditioners (AC) of Baitus Salat Jame Masjid had exploded on September 4. Gas leakage in pipeline and spark set off by a sudden power outage caused the blast.
Bangladesh Fire Service and Civil Defence Deputy Director Nur Hasan Ahmed confirmed this to The Business Standard on Sunday.
"None of the six ACs exploded. The casings and the outer parts of the ACs burnt. But all the materials and substances inside the machines looked fine."
Inspector Ziauddin Ujjal, a member of the Criminal Investigation Department's (CID) probe committee, said the same after visiting the spot on Sunday.
Meanwhile, the district administration, fire service, Titas Gas, CID, and Dhaka Power Distribution Company formed separate probe committees.
The district administration formed a five-member probe committee has been working since early September 5.
Additional District Magistrate Khadija Tahera Bobby said they were primarily looking into gas and electricity connections.
Death toll rises to 24
The death toll from Narayanganj mosque explosion rose to 24 on Sunday as three more victims succumbed to injuries at the Sheikh Hasina National Institute of Burn and Plastic Surgery.
The deceased are the mosque's imam Abdul Malek (60), muazzin Md Delwar Hossain (45), Mostafa Kamal (34), Rifat (18), Rashed (30), Zobayer (18), Jainal (38), Sabbir (21), Kuddus Bapari (72), Humayan Kabir (72), Ibrahim (43), Jonayed (16), Jamal (40), Jewel (7), Mainuddin (12), Rasel (34), Nayan (27), Bahar Uddin (55), Kanchan Hawlader (50), Mizan (34), Nadim (45), Shamim Hasan (45), and Julhas Uddin (30).
Dr Samonto Lal Sen, chief coordinator of the burn institute, confirmed the number and said 13 more people – fighting for life since September 4 – were not out of danger.