A nurse has been charged by police investigating the deaths of five patients at a Stockport hospital.
Rebecca Leighton, 27, is accused of six counts of causing damage with intent to endanger life or being reckless as to whether life was being endangered.
The Crown Prosecution Service says she is alleged to have tampered with medical products, saline ampoules and saline bags at Stepping Hill Hospital.
Ms Leighton is due to appear before Manchester magistrates on Saturday.
The 27-year-old nurse, of Buxton Road, Heaviley, Stockport, also faces one count of theft of medicine from the hospital.
She was arrested on Wednesday by police investigating the deaths of Tracey Arden, 44, Arnold Lancaster, 71, George Keep, 84, Derek Weaver, 83, and Vera Pearson, 84.
'Shocked and appalled'
Mr Weaver, from Stockport, died on Thursday after suffering a hypoglycaemic episode on 11 July - a day after he was admitted from his interim care home with breathing problems.
Ms Arden, of Heaviley, who had multiple sclerosis, died on 7 July and retired photographer Mr Lancaster, of Romiley, died on 11 July.
Mr Keep, of Cheadle, died on 14 July after being admitted to the hospital with a broken hip, while on the same day Mrs Pearson also died.
Police said saline solution at the hospital had been contaminated with insulin, which can cause low blood sugar.
A 41-year-old man remains critically ill in hospital.
Police are also looking at the treatment of eight other patients since 7 July.
Nazir Afzal, Chief Crown Prosecutor for CPS North West, said: "These are serious charges that relate to allegations that Rebecca Leighton tampered with medical products, saline ampoules and saline bags in Stepping Hill Hospital and by doing so endangered the lives of patients.
"We will continue to work with police and provide advice as they continue their detailed inquiries."
Chris Burke, chief executive of Stockport NHS Foundation Trust, said: "We are aware that Greater Manchester Police have charged the 27-year-old female suspect.
"Our thoughts are with the families affected by this incident.
"All of the staff here are extremely shocked and appalled by what has happened and we have ensured there is appropriate support available."