24 hours into Gulistan explosion, possible causes yet to be determined

Although more than 24 hours had passed since the explosion in a Gulistan building on Tuesday that killed at least 19 and injured more than 120 people, the cause of the explosion could not be determined as of last night.

Experts from different government agencies have identified five possible reasons for the explosion – gas from the water tank underneath the building, a septic tank located between two buildings, a broken gas line, methane gas accumulated in the wall, or gas leaked from the propane gas line or from a large generator located in the building.

The bomb disposal unit of the Counter Terrorism and Transnational Crime (CTTC) visited the site and believes that gas had accumulated in a locked room in the building's basement and turned it into a "gas chamber".

Any spark could have caused a dangerous explosion, and the CTTC identified five possible ways in which gas could have accumulated, said Rahmat Ullah Chowdhury, an additional commissioner of the CTTC bomb disposal team.

Rahmat Ullah also told reporters that there is no evidence of sabotage having taken place.

The Rapid Action Battalion (RAB) is suspecting that accumulated gas inside the basement may have caused the explosion in the Gulistan building.

Major Mashiur of the elite force's bomb-disposal unit, told The Business Standard on Wednesday, "After a preliminary probe, we have found that the explosion originated from the basement of the building.

"Accumulated gas, from the building's sewerage or from the supply line of Titas, may have caused the blast."

The RAB official ruled out the possibility of an AC unit causing the explosion.

"To determine the exact cause of the incident, we are trying to recover the CCTV footage of a nearby shop," Major Mahsiur said.

Asked about the slow progress of the rescue operation, he said, "We are currently bringing out the rubble and other items kept inside the building."

Meanwhile, addressing the press at the spot, Titas Gas Director (Operation) Md Salim Mia said, "We didn't find any evidence of a gas leak in our supply lines.

"If that was the case, there would have been a massive fire in the building."

Rahmat Ullah Chowdhury of CTTC said his team could not find any improvised explosive device or any other explosive materials in the building. Furthermore, use of any explosive results in coloured or black smoke, which was not found in the preliminary probe, while the state of injuries also does not suggest any sabotage act.

The status of the burnt victims and the height of the wounds in their bodies suggest gas was flowing three-five feet above the ground, meaning methane gas was most likely behind the explosion.

Asked about the legality of the establishment, Rajdhani Unnayan Kartripakkha (Rajuk) Director (Zone-5) Hafizul Islam said, "We are still searching for the documents related to the building. Only then will I be able to say if it was built, maintaining all the rules, regulations and codes."

According to Dr Syeda Sultana Razia, a professor at Buet, the size of the explosion suggests that it may have been caused by a gas leak – either from a pipeline or an LPG.

In a phone conversation with TBS, she said, "The explosion was significant, and it could not have been caused by sewer gas. I am speaking based on my technical knowledge and expertise in process safety, chemical safety and security, distillation and separation processes, and effluent treatment."

Despite the possibility of a gas pipeline leak, there has been no news about it yet. Dr Razia cited the Moghbazar gas explosion, which was caused by a gas leak. She also said there were no updates on whether the building had sustained any fire damage.

Last night, Rajuk declared the building unusable as nine of its 24 pillars got damaged in the explosion.

It formed a six-member committee, which visited the scene and made the declaration.

No blast victims out of danger yet

None of the victims from the deadly Gulistan blast, who are currently undergoing medical treatment at the Sheikh Hasina National Institute of Burn and Plastic Surgery, are out of danger, said the burn institute's coordinator Dr Samanta Lal Sen.

"Two out of the ten injured people are under treatment in the ICU. Their condition is critical. The rest are not out of danger. Most of their bodies have been burnt," Dr Samanta Lal Sen told The Business Standard on Wednesday.

Many of the victims have multiple injuries caused by the blast and debris.

The victims who are currently being treated at the burn institute are - Md Hassan, 32; Yasin, 26; Md Musa, 45; Khalil,50; Ajam, 36; Oli Shikder, 55; Bablu, 25; Al Amin, 25; Bachchu Mia, 55; Jahan, 25 and Mostofa, 50. Among them, Mostofa sustained deep cut injuries. The other victims have suffered 12% to 98% friction burn.

Two victims are in ICU, two in the Medical High Dependency Unit (MHDU), six in postoperative care, and one has been referred to the Dhaka Medical College and Hospital.

More trapped in rubble

Fire service personnel said there is a possibility a few people may be trapped under the rubble of the building.

"A water tank inside the building's basement may have exploded. People could have fallen into the tank as well," Lt Colonel Tajul, director of operations at the fire service, told The Business Standard.

Earlier on Sunday, three people were killed and dozens injured when a blast rocked the capital's Science Lab area.

It had been suspected that the source of the explosion was either an AC unit or a gas cylinder, but the CTTC Bomb Disposal Unit later confirmed that the blast happened due to accumulated methane gas.

The tragic incident occurred a day after a blast in an oxygen plant in Chattogram's Sitakundu that claimed six lives.