Stepping Hill Hospital deaths: Nurse on murder arrest 20 July 2011 Last updated at 10:03 GMT

 A nurse has been arrested on suspicion of murder after the deaths of three patients at a hospital in Greater Manchester.

The woman, 26, is being questioned after two men and a woman died at Stepping Hill Hospital in Stockport.
She was arrested at her Stockport home. Police believe insulin was deliberately injected into saline containers.
Sixty detectives have been involved in the inquiry and officers have questioned more than 50 people so far.
Tracey Arden, 44, 71-year-old Arnold Lancaster, and George Keep, 84, have all died at the hospital in the past month.
A fourth patient, a man in his 40s, remains critically ill.
Greater Manchester Police believe the sabotaged saline containers were used by at least two wards, A1 and A3.
Deaths 'unexplained' The force said they were working on the assumption the contamination had taken place on the site.
The four patients are among a total of 14 whose treatment since 7 July is being examined by police.
Dr Chris Burke, chief executive of Stockport NHS Foundation Trust said: "We are aware that Greater Manchester Police have made an arrest this morning of a 26-year-old female.

Tracey Arden, George Keep and Arnold Lancaster have all died at Stepping Hill in the past month

"As the police are continuing with their enquiries, we are unable to provide any further details, but it is important to stress that no charges have been made at this stage."
Detectives were called to the hospital after an experienced nurse reported a higher-than-normal number of patients on her ward with "unexplained" low blood sugar levels.
Officers found insulin had contaminated a batch of 36 ampoules in a storeroom close to ward A1.
Security has been increased on the hospital site and staff have been told to work in pairs when they check or administer drugs.
Senior NHS bosses at the hospital are having daily meetings with police.
Insulin is always stored in a fridge in a locked treatment room but saline has also been locked away, as a result of the incidents.
The three deaths are being treated as unexplained until the results of further pathology tests are confirmed.
Contaminated bag South Manchester coroner John Pollard has opened and adjourned inquests into Ms Arden, Mr Lancaster and Mr Keep.
Police have said a bag containing saline solution was found damaged in the maternity ward but it had not been contaminated.
Assistant Chief Constable Ian Hopkins, leading the inquiry for Greater Manchester Police, said: "It is important to stress that this product has not been contaminated and, in fact, the damage could very well be accidental, as can happen quite easily in a busy hospital environment.
"Extra security measures are in place across the hospital and staff continue to be vigilant, which of course is to be expected.
"Due to heightened awareness, staff are alerting police to anything they feel might be suspicious or relevant to the investigation and to date there has been no further contamination of any product since the control measures were introduced."