A woman and four emergency workers are being treated in a London hospital after being exposed to a "hazardous substance".The woman was taken to Croydon University Hospital by the London Ambulance Service (LAS) after reports she had ingested poison.Two Metropolitan Police officers and two members of staff from the LAS were exposed to the substance and are under observation.Parts of the hospital were initially closed off, but the incident has since been stood down.A police spokesperson said: "Poli

A woman and four emergency workers are being treated in a London hospital after being exposed to a "hazardous substance".The woman was taken to Croydon University Hospital by the London Ambulance Service (LAS) after reports she had ingested poison.Two Metropolitan Police officers and two members of staff from the LAS were exposed to the substance and are under observation.Parts of the hospital were initially closed off, but the incident has since been stood down.A police spokesperson said: "Police were called at 03:46hrs by London Ambulance Service to reports of a woman having ingested poison at an address in Thornton Heath.The London Ambulance Service has also confirmed two of its members of staff are being treated for exposure to harmful chemicals.