A HUGE fire at a music bar in Bangkok has left at least 27 people dead and 25 hospitalised in a critical condition.

Photos from the Rong Beer Na Ladprao bar in a northern district of Bangkok showed people fleeing as flames shot out of the single-storey building and thick black smoke billowed into the sky.

City officials said the fire had broken out shortly before midnight on Sunday and it had taken firefighters about half an hour to bring it under control.

By daylight, the site was cordoned off as forensic officers combed through the burned remains for clues as to the cause.

National police chief Kittharath Punpetch said most of the dead had been found trapped in windowless toilets near one of the rear exits from the bar, where they may have sheltered to escape the flames in the hall.

He said people may have been prevented from reaching the exit by a table set up in the hall to sell confectionary or because it was too dark to see it.

Access to another exit near the kitchen might also have been narrowed by shelving units and lockers, said Mr Kittharath. There were signs that at least some of the exit doors might have been locked shut, he added.

Investigators are focusing on the ceiling above the stage, where they found materials that may have been used as decorative elements, he said. Police will examine whether flammable materials were used and how electrical wiring was installed across the ceiling.

According to Bangkok’s Erawan emergency services centre, 73 people were injured, with 25 in a critical condition. Bangkok Governor Chadchart Sittipunt said most deaths were caused by smoke inhalation.

On January 1 2009, 67 people were killed and more than 200 injured in a blaze at the Santika nightclub in Bangkok during a new year celebration.