Investigating officers on Tuesday recorded the statement of Athulya Uday Kumar, 24, who was injured in the cylinder blast in a lab in IISc last Wednesday. Athulya allegedly told the police that the blast was accidental and all that he remembered was that Manoj Kumar, who died in the explosion, was setting up the cylinder with a mix of hydrogen and oxygen, for the experiment they were working on.

According to BK Singh, Additional Commissioner of Police (East), Athulya said: “Manoj was an experienced technician and like every time, he was setting up the cylinder for the experiment when the blast suddenly happened. I don't remember anything after that.”

Police have also taken the statement of officials from the company which regularly supplied cylinders to the lab. “We found no fault with the supplier, who has only done his job.”

Prima facie, it looks like a case of an accidental blast, but we are waiting for reports from the Forensics Science Laboratory, the officer said.

Athulya was discharged from M S Ramaiah Memorial Hospital on Monday, with doctors saying that he would have to follow up with plastic surgeons as an outpatient.

Another survivor, Naresh Kumar, 33, was taken off the ventilator and is stable, but still in the Intensive Care Unit.

Dr Naresh Shetty, president, M S Ramaiah Memorial Hospital, said, "While Athulya has been discharged and sent home, Naresh will go for surgery on Wednesday as he has an open fracture on his leg, which will take four months to heal. He will be brought back to the ICU after the surgery."

Kartik Shenoy, 25, was also taken off the ventilator, but doctors said that he has a tough road ahead with rehabilitation, after he pulls through.

"Kartik was taken off the ventilator and there is no immediate threat to his life. A CT scan scheduled for Wednesday will reveal more. There were metal pieces in his stomach that got locked in, so there was foreign body infection. He is being given oral fluids. He will have a tough road ahead," added Shetty.