ZURICH Swiss police said six people were taken to hospital on Tuesday following the leak of a corrosive liquid at a Novartis pharmaceutical production site in Schweizerhalle near Basel.
Police said in a statement that the leak occurred at around 1040 GMT on Tuesday and affected 13 people, six of whom had to be taken to hospital, suffering from the effect of inhaling the chemical.
Police said there was no danger for people outside the Novartis site, about 6 km outside the city of Basel.
Five of those taken to hospital work for an external cleaning company, while one person is a Novartis employee, police said.
Firefighters, paramedics and police were on the scene.
Novartis said it had no additional information on the accident. The Schweizerhalle site manufactures drugs including those used to treat hypertension like blockbuster Diovan.
In November 1986, a fire in a storage building used for pesticides and other agricultural chemicals at the Schweizerhalle site released agrochemicals into the air and polluted the Rhine river, turning it red.
At the time, the site belonged to Sandoz, which merged with Ciba-Geigy to form Novartis ten years later.
(Reporting by Caroline Copley and Emma Thomasson; Editing by Helen Massy-Beresford)