A tyre burst could not have caused Saturday's bus accident on Samruddhi Expressway, in which 25 persons were charred to death, as there were no pieces of rubber or tyre markings at the scene, the Amravati Regional Transport Office (RTO) stated in its report.

The RTO report, which was based on survivors' accounts, said there was no evidence (rubber pieces of tyres after burst) or tyre markings at the spot, and the impact marking was on the wheel disc, which was bent, and not on the tyre itself.

A bus carrying 33 passengers from Nagpur to Pune on the Samruddhi Expressway overturned and caught fire in Sindkhedraja in Buldhana at 1.32 am, killing 25 occupants.

As per the details provided by one of the survivors, the bus dashed into a steel pole on the right side of the road, leading to the driver losing control of the vehicle, which then hit the divider, the report said.

It further said the impact of the front tyre hitting the divider was so severe that it caused the front axle assembly to dislocate from the bus chassis.

The right side of the vehicle, where the diesel tank is located, again hit the divider, the impact cleaving the bus body, the report said.

After the front axle assembly got dislocated, the front portion of the bus hit the road and the resultant friction generated heat and fire (as engine oil temperature was also high since the bus was in on mode), the report said.

The vehicle then overturned on its left side after getting dragged due to the absence of the front axle, which caused more heat resulting in a blaze, it added.

The bus turning turtle on its left side blocked the passenger entrance-exit and the loss of alignment of the vehicle due to the impact of the accident also made the emergency door inoperative, it said.

The report, however, noted that speed may not have been a cause of the accident since the bus took two hours and 24 minutes to cover the 152-kilometre stretch from the entry point of the Samruddhi Expressway to the spot in Sindkhedraja where the accident took place.

The bus entered the Expressway at 11:08 pm and the accident took place 152 kilometres away at 1:32 am, which means the average speed of the bus was 70 kilometres per hour, the report said.

The bus was on its way from Nagpur to Pune and had started its journey from Vidarbha's largest city at 5pm on Friday.

It was on the Nagpur-Wardha-Yavatmal-Darwha-Karanja(Lad)-Samruddhi Expressway-Pune route, the report said.

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