Insulin poisoning at hospital in Stockport claims fourth and fifth victims Two more patients have died of suspected insulin overdoses at a hospital as a 27-year-old nurse continues to be interviewed by police on murder charges. The patients fell ill at Stepping Hill hospital in Hazel Grove, Stockport, where three other patients have died. Tests are continuing to determine if saline that had been injected with insulin was directly responsible for the deaths of Tracey Arden, 44, 84-year-old George Keep, and Arnold Lancaster, 71. Detectives are questioning Rebecca Leighton, who works as a nurse at the hospital. She was arrested at her flat in the Heaviley district of Stockport at 6am on Wednesday. Sixty detectives from Greater Manchester police are working on the case. The treatment of 14 patients since 7 July on two acute medical wards – A1 and A3 – is being examined by police. Thirty-six bags of saline in a storeroom were found to have been sabotaged with insulin. On Tuesday police said the person responsible could still be at the hospital. Detectives can apply for an extension to continue questioning Rebecca Leighton if they need more time. Officers were first called nine days ago after an experienced nurse noticed unexpected drops in blood sugar levels in a large number of patients on the ward. Staff have now been told to work in pairs when checking and administering drugs. A single keyholder has to be asked for access to locked drugs cabinets. Police have said a product containing saline found damaged in the maternity ward at Stepping Hill was not contaminated, according to preliminary tests. Inquests into the deaths of three patients have been opened and adjourned at the request of the police. Tracey Arden had been diagnosed with multiple sclerosis 12 years ago. She had been admitted to the hospital on 7 July suffering from associated illnesses. Her parents, who live nearby, said she had been in good spirits when they left but within two hours began to deteriorate. Hospital staff called and told them to return urgently but she died before they arrived. Retired businessman George Keep was admitted to the hospital with a fractured hip after a fall on 27 June and had seemed to be recovering initially. He ran his own house maintenance firm and was described by relatives as a keen gardener and very strong for his age. His health suddenly deteriorated at the hospital and for six days doctors struggled to keep him alive. He was given blood and put on a saline drip for hydration but died last Thursday. Retired photographer Arnold Lancaster, of Romiley, had worked for the Stockport Express. He died on 11 July. The hospital has said it is not concerned about the health of nine other patients who were affected by the saline. Dr Chris Burke, chief executive of Stockport NHS Foundation Trust, said the trust was unable to comment further or provide any more details because of the police investigation. The Nursing and Midwifery Council confirmed that Rebecca Leighton had been arrested. Friends expressed their shock. It is understood her mother, Lynda, is a senior manager at the hospital responsible for training nurses. Other hospitals across the north-west had been warned to be vigilant. Crime NHS Health Helen Carter guardian.co.uk