Bluewater chemical leak sees seven treated in hospital 29 April 2013 Last updated at 17:44 Seven people were taken to hospital after a chemical leak at a store at one of the UK's largest shopping centres. Ammonia is thought to have leaked from a fridge at John Lewis at Bluewater shopping centre in Greenhithe, Kent. The people were taken to Darent Valley Hospital in Dartford, while about 20 others, all believed to be staff, were assessed by first aiders at the scene, the ambulance service said. The alarm was raised at about 11:45 BST and the shop was closed for an hour. People were treated for symptoms including sore throats, headaches and stinging eyes. None were members of the public, a spokesman for South East Coast Ambulance Service said. "The fire brigade were called to investigate a suspected ammonia leak from a small fridge located in a demonstration area in the basement," said a spokeswoman for John Lewis. The shop was evacuated and reopened an hour later. She said six of the people taken to hospital were members of staff and the seventh was a representative from the company which owned the fridge. Three had been discharged by late afternoon, two were undergoing treatment and two others were being assessed by doctors. Kent Fire and Rescue Service said it sent three fire engines to the site and firefighters and Kent Police officers helped evacuate the store.