A huge blast on a leaking gas pipeline in Belgium yesterday sent giant fireballs into the air and catapulted bodies hundreds of metres in the biggest industrial disaster in the country's recent history.

At least 15 people were killed and more than 100 injured when the explosion ripped through the underground pipeline in the industrial zone of Ghislenghien, near the town of Ath, 40 kilometres southwest of Brussels.

The chain of explosions, described by one witness as a "mini-Hiroshima", destroyed two factories, leaving a large crater in their place. Bodies and debris were scattered over a 500-metre radius around the scorched disaster site.

"There were bodies in parking lots, in the fields; burnt-out cars in an area half-a-kilometre wide," fire department spokesman Francis Boileau said. "It looks like a war zone.

"There were people fleeing who I am sure we will find too late in the fields several hundred metres away," he added.

The regional civil protection agency gave a provisional toll of at least 15 dead and more than 100 injured. It said the figures could rise because 24 people were severely burned.

The explosion tore through a section of the pipeline carrying gas from the Belgian port of Zeebrugge to northern France while repair men worked to plug a leak, a spokesman for the agency said.

Belgian utility giant Electrabel said one of its employees died and another was severely injured.

Belgian Prime Minister Guy Verhofstadt cut short a holiday in Italy, and will join Belgium's Prince Laurent on a visit to the victims and at an emergency cabinet meeting later in the day.

Condolences began to arrive from abroad with the Pope and French President Jacques Chirac offering their sympathies to the victims and their families.

Interior Minister Patrick Dewael said several of the dead were firefighters who were setting up a security perimeter after the leak was reported.

One witness, Olivier Rampelberg, who lives about three kilometres from the blast site, said he heard a sound like a thunderclap shortly after 9 a.m. (0700 GMT).

"It sounded like continuous thunder," he told RTBF television. "Then little grains of scorched earth rained down."

Another witness told a radio reporter: "It sounded as if a plane had crashed. All the windows shook... it was terrible."

Fluxys, which runs the country's network of gas pipelines, confirmed the cause of the blast.

"There was a gas leak, which led to an explosion," spokesman Christian Otto said.

Fluxys employees were not among the injured, he said. It was the deadliest gas explosion since 1967, when a tanker truck carrying liquid gas exploded, killing 22 people.

In the country's worst industrial catastrophe, 262 people died in a mine explosion at Marcinelle in 1956, including 136 Italian immigrant workers.

Police closed the adjacent €429 motorway, the main artery linking Brussels to the French city of Lille and the Channel port of Calais.

Residents were ordered to stay indoors because of the smoke, although officials stressed there was no chemical hazard.

Fluxys, jointly owned by Royal Dutch/Shell, French utility Suez and a group of municipalities, said it had halted pumping along the line and taken measures to keep supplying customers including Gaz de France.

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