Firemen carry out a BSNL employee who was trapped inside the Burrabazar exchange. Picture by Kishore Roychowdhury

Calcutta, Aug. 28: Over 35,000 telephone lines — mainly numbers starting with 2268 and 2269 — are feared to have been affected this evening as a fire broke out at the Burrabazar Telephone Exchange on Central Avenue.

According to a senior BSNL official, 20,000 direct lines and another 15,000 of a Remote Line Unit — they have switching functions and are treated as exchanges — that fall under the Burrabazar exchange could have gone dead.

“However, the disruption will not be for very long as all exchanges are centrally controlled and we will try to make temporary arrangements to make the numbers function at the earliest,” the official said. He did not spell out a specific time frame.

It took 15 fire tenders and more than two hours to bring the fire under control. Dense smoke hung in the area and a pungent smell filled the air as smoke belched out from the four-storey building.

Rajeev Kumar, the deputy commissioner of police (central division), said preliminary investigation suggests a short-circuit in the electrical wiring on the third-floor was the trigger and the flames hissed to the ground floor, setting the main cable box ablaze.

“The fire was easily controlled and subsequently there was more smoke than fire. But we were tense as quite a few persons — several staff members and a BSNL driver’s family — were trapped inside the building. However, all of them have been rescued and sent to Calcutta Medical College and Hospital,” Kumar said.

“Few staff members were present when the fire broke out as it was closing time. On seeing the fire, an on-duty traffic sergeant of Jorabagan Traffic Guard, K.P. Das, entered the building and helped several of the trapped to get out. But as he climbed to the second floor, he got trapped,” said Bibhash Ghosh, the divisional officer of the fire services.

Officials of the fire department reached the spot within minutes and broke open the door at the rear to rescue a few others from there. “But the Hajis — the driver, his wife and three children, aged between 10 months and six years — and two others who had climbed to the terrace on seeing the fire were trapped,” said an official of Jorasanko police station.

“Another staff, Dipak Sadhukhan, who had gone to the second-floor toilet, was found unconscious due to the heavy smoke. We rescued him by cutting the grille of the bathroom window. He was sent to the hospital where he is undergoing treatment,” Ghosh added.

The fire department officials first tried to rescue the trapped using the mechanical ladders, but failed. In the meantime, some fire fighters made it to the terrace and rescued all the seven persons.

“We had to cover their face with wet cloth so that they did not feel suffocated by the dense smoke which we had to fight on our way,” a fire department official said.

The south-bound flank on Central Avenue was blocked for more than two hours.