The mother of a man found dead in his own home requested a police investigation to be carried out into her son's death, an inquest has heard.

The body of Jonathan Cox, 29, was found in the living room of his Union Street flat in Norwich on March 30, 2012.

An inquest into the cause of his death started in Norwich in front of senior Norfolk coroner Jacqueline Lake yesterday and heard officers had found his body after being called to his home because of concerns for his safety.

They found packets of medication near to Mr Cox – who was receiving medication for back pain – and two empty bottles of vodka.

An initial post-mortem examination concluded cause of death was aspiration pneumonia and overdose of morphine (prescribed medication).

A police inquiry was launched after Mr Cox's mother, Jayne, requested her son's death be investigated because of concerns about the amount of morphine he had been prescribed.

The pathologist reviewed the case and concluded cause of death was due to acute pneumonia but could not be confident of the underlying cause.

He said it could be as a result of the high level of morphine or the result of an infection caught in the community.

A statement read on behalf of Det Insp Gary Bloomfield, from the Norfolk and Suffolk Major Investigation Team (MIT), said the investigation into the death of Mr Cox, who was also being treated for mental health problems, found he had 'lied' to get more medication.

It found 'no evidence to support an unlawful killing allegation whatsoever' and 'no evidence' of a gross negligent manslaughter offence.

The inquest heard Mr Cox told doctors on more than one occasion he had lost his medication and in February 2012 was warned that no further repeat prescriptions for lost or stolen medication would be issued.

The inquest continues.