Calcutta, March 24: A locked terrace and an emergency spiral staircase ending two floors short of the top which was overlooked by the civic body had sealed the escape route of many who were charred to death in Stephen Court yesterday.

The official death toll in the Park Street fire leaped to 24 overnight and between 10 and 20 people were unaccounted for till Tuesday night.

As many as 17 of the charred bodies brought down from the sixth floor of the seven-storey Stephen Court till late tonight were found piled up on a tapering staircase leading to a locked grille, suggesting a last-ditch lunge for air and the terrace that could have led them to the safety of an adjoining block.

“Some of these victims were found face down on the stairs with their hands outstretched, as if trying to reach the grille. It spoke of their desperation to reach the terrace. Many of them may have died of suffocation before the flames reached them,” Gopal Bhattacharya, the director of fire services, said.

Most fifth and sixth-floor residents in the block facing Middleton Row didn’t stand a chance because all possible escape routes were sealed.

The rights to the terrace of Stephen Court, a sprawling piece of real estate embroiled in ownership tangles matching its labyrinthine interiors, lie with builder Sanjay Bagaria. On the afternoon of the tragedy, the key to that terrace shared by four blocks was with one of the caretakers of the building, Tarun Bagaria (not related to his employer).

“We had requested Tarun Bagaria (a resident of flat No. 7A on the sixth floor) several times to give duplicate keys of the terrace to representatives of the four blocks. If only he had listened to us,” said D.K. Bibra, a resident of Block III.

Bibra said the 10-odd cellphone towers on the terrace powered by diesel generators added to the list of fire hazards. “We believe the terrace was closed to residents primarily to protect these towers.”

The other potential life-saver, the spiral staircase, ended midway at the fourth floor because that was the last stretch of the original building. When two floors were added in 1984, the stairway was not extended. The Calcutta Municipal Corporation (CMC), the authority that should have spotted the truncated staircase and insisted on its extension before “regularising” additions to the building, did not do so apparently because of a “loophole” in the law.

The fourth floor was added in the 1930s without permission. In 1984, two more storeys were illegally added. In 1984, the CMC slapped a notice and eventually “regularised” the additions after the payment of penalties.

The addition of the three floors meant that Stephen Court had crossed the 18-metre limit, beyond which a fire-safety certificate is mandatory. But the “loophole” — “regularised” buildings need not apply for the certificate — allowed all concerned to look the other way, a CMC official said.

Ibrahim Safvi, a sixth-floor resident of one of the blocks that escaped the blaze, said that not extending the emergency staircase was a big handicap. “There was little chance of anybody succeeding in reaching the fourth floor from the fifth or sixth through the main staircase and taking the spiral stairs to the courtyard and the parking lot. There was too much smoke all around and it was dark as well.”

The civic body’s oversight hammered in another nail. The main staircase of the top two floors — those regularised by the CMC — is too narrow to facilitate easy movement.

“The width of the staircase for the top two floors that were added in 1984 is half of that in the rest of the building,” said Sarla Butta, a resident of Stephen Court for 47 years.

Changing lifestyles inside the old building added to the pressure. “The number of airconditioners and other appliances running together has trebled since the top two floors were added. But the building still does not have an additional CESC transformer to bear the load,” Bibra said.

An electrical short-circuit in the elevator shaft of Block II is suspected to have triggered yesterday’s fire, though forensic officials have yet to give their verdict. “Indiscriminate installation of airconditioners contributed to the fire,” the fire chief said.

The incompatibility of commercial establishments and residences was another factor. “The top two floors house mainly offices with plywood partitions and false ceilings that helped spread the flames,” said a resident.

Stephen Court has never had a registered flat-owners’ association to protect their rights. Two years ago, there was a fire in a meter box but it was put out in the nick of time.