The parents of newborn twins who died after being prematurely born at a scandal-hit hospital, sparking an external investigation, have said they are "deeply upset and distressed" by the tragedy.
Alfie and Harry McQuillin died on November 1, two days after their birth at Stafford Hospital, which has been heavily criticised for appalling standards of care and is the subject of a public inquiry.
A member of staff has been suspended and an independent paediatric doctor has been tasked with conducting an investigation into the circumstances.
In a statement released by Staffordshire Police, Phillip McQuillin and Ami Dean, from Stafford, said: "We are deeply upset and distressed by the deaths of Alfie and Harry.
"A full investigation into the circumstances has been launched, which should now be allowed to run its course. We would ask the media to respect our privacy as we try to come to terms with what has happened."
Police said preliminary tests indicated that the boys, who were born at 27 weeks, died because they were so premature "rather than as a direct result of any medical treatment".
According to unconfirmed reports, health officials are examining whether the twins were given incorrect doses of a drug.
A police spokesman said: "Post-mortem examinations by a Home Office pathologist proved inconclusive and further tests will now be carried out. However, preliminary results suggest that the twins died because of their prematurity rather than as a direct result of any medical treatment."
The babies died at the University Hospital of North Staffordshire after being transferred from Stafford Hospital.
An inquest into the deaths was opened and adjourned by south Staffordshire coroner Andrew Haigh on Monday.