Officials say the hall is licensed to hold only 150 people.

"This means that the security arrangements - width of the doors, exits and so on - are suitable for only that amount of people," explained fire brigade engineer Anders Wallin to the Dagens Nyheter newspaper.

The police said there were only two fire exits, one of which was blocked at the time of the accident.

Rescuers were at the site in five minutes

Leader of the rescue operation, Lennart Olin, said there had been an inspection in the hall in April 1997, when the exits and and other arrangements had matched the regulations.

The hall was rented by the local Macedonian immigrant association which had hired it out for the night to eight party organisers.

The police have so far declined to identify these people, and the paperwork with their names is thought to have been destroyed along with the building.

There was some fire extinguishing equipment in the hall, but none of it had been used. It is uncertain if the organisers knew about the security arrangements or regulations for the hall.

Cause still unclear

The cause of the fire, which destroyed the whole first floor of the building, is being investigated.

Fire brigade engineer Bo Wahlström said the quick spread of the flames could indicate arson, or that the fire had burned undetected for a time before exploding.

But the police said there was no evidence at this stage to suggest that arson was to blame.

It has also been suggested that the fire was started by an electrical spark.

According to one eyewitness, the blaze spread from the ceiling; another said it started from the DJ's equipment.