The authorities also believe gas that accumulated inside the mosque after pipeline leaks may have triggered the blast that caused the window glasses, some with the frames, fly onto the street and burnt ceiling fans, electric switch boards, and wires.
The air conditioners on the ground floor appeared to have melted after six units of the Fire Service and Civil Defence watered the two-storey Baitus Salat Jame Masjid in the Sadar Upazila’s Pashchimtalla neighbourhood.
The explosion took place when the Muslim worshippers were about to end their Isha prayers. Many of them were saying Sunnah (optional) prayers after Fard (compulsory) during the incident, Narayanganj Superintendent of Police Mohammad Zayedul Alam said.
Citing locals, Fatullah Police Station OC Shafiqul Islam told bdnews24.com more than 50 people were offering their prayers during the explosion.
“They ran for safety after the sudden explosion with a large bang. Many of the victims were rolling on the street to extinguish the flames on their bodies,” he added.
All of them were in “critical condition”, said doctor Samanta Lal Sen, the institute’s coordinator.
Kamrul Ahsan, an official at the fire service’s Control Room, said they sent the firefighters after being informed around 8:45pm.
It took around half an hour for the fire crews to bring the flames under control, he said.
The fire service has formed a committee headed by Director Lt Col Zillur Rahman to investigate the incident.
Deputy Director Debashis Bardhan said the exploded air conditioners had the capacity of 1.5 tonnages each.
“They exploded at a time. But we are checking if there is something else,” he added.
The fire service found Freon gas, which is used in air conditioners, at the mosque after the blast, he said.
Mohammad Rony, a witness, said he saw many of the victims with burn injuries rolling on the street.
Some of the locals who reside near the mosque alleged there have been leaks in the Titas gas pipelines in the neighbourhood. They suspect gas accumulated inside the mosque that caused the explosion.
Abdullah Arefin, a fire service sub-assistant director, said they also saw leakages in Titas gas lines in front of the mosque.
“Investigation is needed to confirm what actually happened,” he added.
[More on this developing story soon]