The closure of vestibule in coach B1 of Bangalore-Nanded Express that was gutted early Saturday morning may have prevented escape options for the passengers, who were already choking owing to the smoke.

According to 31-year-old Umesh, who survived the fire accident, the vestibule was closed at the time of the accident. “Since the vestibule was locked, we had only two doors to escape and were unable to open the doors too. Passengers escaped from the toilet windows that were broken open,” he told reporters on Saturday. Three relatives of Mr. Umesh are still missing.

However, a railway official defended the shutting down of vestibule in the train. “We have been following this practice of shutting down the vestibule to prevent theft and unauthorised movement between the coaches in the night. They are closed by our staff from 10 p.m.”

Though vestibule should have been in a position to be opened, it, unfortunately, did not open during the accident, another senior official in South West Railway, said. Many may have choked to death in smoke and later charred, the official said.

Even as preliminary reports have identified short-circuit in the air conditioning unit of the coach for the inferno, a SWR official pointed out that the fire would have been seen on top of the coach if it was a short circuit in the AC, and not inside.

For, the new AC 3-Tier model bogies deployed since 1997 have the roof-mounted air conditioning units, and any short circuit would have triggered fire on the roof. “If it was fire from AC short circuit, then fire would have been noticed on roof. However, the photographs and initial reports suggest that the fire started inside the compartment. Prior to 1997, coaches had AC equipment inside the bogies,” the source said.

The compartment that was engulfed by a fire that rapidly spread causing death of 26 passengers in Anantapur district in early hours of Saturday had roof mounted airconditioning unit, the source said.

“Fire may have spread rapidly inside the compartment since there were enough combustible materials such as blankets, bags and others. It may have also spread after passengers broke open the door, allowing lot of air inside the compartment that enabled the fire to spread.

The source blamed poor maintenance of the coaches in the light of shortage of staff and shortage of time to inspect the coaches before the train begins the journey.