French factory blast kills 18

The blast had the force of an earthquake

At least 18 people have been killed in a huge explosion at a petrochemical plant in France.

French media reported that about 650 people have been taken to hospital, of whom 49 were seriously injured.

I was on a freeway going towards the airport and then I saw a big cloud, a big, yellow mushroom that seemed to be sulphur

Local businessman

The AZF factory, which is the biggest fertiliser producer in France, is about 3km (two miles) outside the south-western city of Toulouse.

French President Jacques Chirac and Prime Minister Lionel Jospin both visited the scene.

An inquiry is under way, but authorities believe it was accidental.

French radio reported that some of the workers had made a mistake while mixing chemicals.

'Plane exploding'

Hundreds of residents ran into the streets in panic and police sealed off the area, fearing a cloud of fumes seen after the explosion could be poisonous.

People later reported experiencing stinging eyes and throats and a strong smell of ammonia.

Part of the factory was completely destroyed in the explosion.

More than 200 people are believed to be injured

Witnesses said the force of the blast blew out windows and cut telephone lines to the area.

Sandra Muller, a mother of three, told the Associated Press: "We thought it was a plane exploding. All the houses trembled."

A bypass runs next to the factory, and dozens of drivers caught the full blast.

A local businessman told French radio: "I was on a freeway going towards the airport and then I saw a big cloud, a big, yellow mushroom that seemed to be sulphur."

Local residents reported hearing two explosions. The director of a neighbouring ammunition factory told Reuters the blast had caused a second, smaller explosion at the armaments plant but there were no injuries.

An electrical store next to the AZF factory collapsed shortly after the blast, and there were reports that a Hyundai auto dealership nearby collapsed crushing the cars inside.

Many drivers caught the full blast

Authorities shut Toulouse airport and the subway as a precaution and a nearby industrial area was also closed off.

BBC correspondent Christopher Buckman, who was at the scene, says the explosion measured 3.2 on the Richter scale - the equivalent of a small earthquake.

The factory is now little more than a twisted tangle of metal and rubble, he says, and thick black fumes are emerging from the wreckage.

The explosion left a crater 50m wide.