A National Security Guard team on Sunday visited the Mall Road eatery in Shimla where a gas leak apparently led to a blast, killing one person and injuring 13 more.
The blast occurred on Tuesday evening at Himachali Rasoi restaurant, known for serving Himachali cuisines, located in Middle Bazaar adjacent to the fire brigade office in the heart of the city.
The police said the blast was apparently caused by a gas leak.
A 16-member team of the NSG's national bomb data centre inspected the site, collected evidence from the blast spot, examined the evidence collected by the special investigation team probing the case and also interacted with those injured, besides the forensic experts who initially collected the samples.
Director general of police Sanjay Kundu told PTI earlier in the day that the place where the blast occurred was sensitive as it is near the police reporting room.
The NSG specialises in this field and their services are being availed to determine the cause of the blast according to the standard operating procedure of the government, he added.
Created in 1988, the NBDC is the apex national agency for post blast investigation which works under the NSG.
Keeping in view the sensitivity of the case and to ensure a thorough and expeditious investigation, the DGP had requested the additional secretary of the Counter Terrorism and Counter Radicalisation Division under the Union ministry of home affairs to depute the PBI team of the NSG to unearth the cause of the blast, a statement issued here said.
On July 19, Kundu visited the blast site and said preliminary investigation and forensic examination have pointed out that a gas leak led to the blast.
According to the statement of the injured people, a gas leak from two LPG cylinders led to the blast but more casualties were averted as the place was closed for maintenance.
Shimla superintendent of police Sanjeev Kumar Gandhi said people in the vicinity of the eatery had complained of a gas leak before the blast.
However, suspicion is being raised due to the high intensity of the blast that shattered windows of several shops and houses in the vicinity and the sound of the explosion was heard miles away.
The SIT constituted to probe the blast has registered a case of endangering life, causing hurt and causing death by negligence under sections 336, 337 and 304A of the IPC.
Meanwhile, Bharatiya Janata Party media in-charge Karan Nanda, who along with other shopkeepers are demanding a high-level investigation into the matter, said they were confident that the NSG would dig out the truth about the blast.
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