Ten people have died and more than 200 hurt after a massive explosion at a fertiliser plant in France.
A total of 50 are reported to be seriously injured.
Officials have sealed off the industrial area just south of Toulouse, evacuated schools, closed the airport and the underground rail.
They are also warning people to stay at home as a precaution.
French premier Lionel Jospin has rushed to the city from Paris.
There were early fears that plumes of smoke drifting across the city could be toxic, though officials say this appears not to be the case.
"We thought it was a plane exploding," said mother-of-three Sandra Muller who lives about 15 miles from the site. "All the houses trembled."
A regional official, Hubert Fournier, said "there are numerous victims surely, but it's impossible to say how many."
He wouldn't comment on the cause of the explosion, which occurred at about 9.30am (Irish time) at the AZF chemical plant, the biggest fertiliser producer in France and Europe's third-largest.
Media reports said the blast appeared to be accidental but authorities are not completely sure.