Deshapriya Park: A fire broke out at Priya Cinema in the middle of the night show of Fanney Khan on Sunday, triggering anxious moments before around 35 people in the audience were safely evacuated along with the owners' family that occupies the upper floors of the building.

Officials of the fire services department said an electrical short circuit in a momo counter on the ground floor of the cinema triggered the fire around 10.15pm.

Smoke quickly spread to the first floor as flames engulfed the momo counter, a witness was quoted as saying. Five fire engines took around an hour to douse the flames. The windowpanes on the first floor were shattered to let the smoke out.

The family of Arijit Dutta, who owns Priya Entertainments Pvt Ltd, had moved to the terrace when smoke filled the rooms of their house. They were brought down after the smoke was controlled.

Firefighters broke the lock on one of the gates leading to the floors to which smoke had spread. Members of Arijit's family used fire extinguishers to break the lock on a grille, an official said.

"We are all safe. The fire spread from a momo outlet. We were all on the terrace. Arijit's office is worst hit and our room is all smoky," said Arijit's wife Esha.

Debasish Kumar, mayoral council member in charge of parks and gardens in the Calcutta Municipal Corporation, said the family had been asked to come down when the audience was being evacuated. "They said they would wait upstairs. Since the fire had been controlled by then, we didn't force them to come down immediately."

The night show had started around 9.15pm. Prateek Bose, who was in the audience with some friends, recalled "smelling something burning" around 10.15pm and sensing that something was amiss.

"I stepped out of the hall and urged my friends to do the same," he said. "At the staircase, we found some ushers rushing towards the entrance to the hall and shouting for us to get out of the building," Prateek said.

Chand Kumar Mondal, a projector operator at the theatre that has been screening films since May 1959, said he looked down from his first-floor office to find thick black smoke curling in from below. "I ran for my life," he said.

Portions of the building turned black because of the smoke.

Mayor Sovan Chatterjee, who visited Priya Cinema soon after hearing about the fire, said an investigation into the cause of the fire would start on Monday.

"Forensic experts will visit the cinema to ascertain the origin of the fire. If the trigger was an electrical short circuit, we will investigate whether there was any lapse on the part of the momo outlet," said an official of the fire services department.