A catalogue of failings led to a paranoid schizophrenic with a long history of mental health problems killing his mother at his family home in Norfolk, an independent report has concluded.

Darren Weatherley slashed his mother's throat with a knife in Needham, near Harleston, in 2010, a week before he was due to have a follow-up appointment with mental health services.

An independent review found that he was discharged from the care of a care coordinator from Suffolk Mental Health Partnership NHS Trust in September 2009 and was due to have an outpatient follow-up every two months. However, due to a clerical error, he was not sent an outpatient appointment until five months later for an appointment on March 22.

On March 15 2010, he killed his mother Carol Weatherley, 53, after hearing voices in his head to kill his family.

The findings of an NHS commissioned report, published yesterday, said Mr Weatherley should never have been discharged from the care of the community mental health team (CMHT) and a care programme approach (CPA).

It concluded: 'What emerged from our investigation was a team struggling with operational changes, staff sickness, a pressure to keep patients moving through the system and limited resources given the large geographical area it was expected to cover.'

Authors of the report made two recommendations to officials from Suffolk Mental Health Partnership NHS Trust, which merged to become Norfolk and Suffolk NHS Foundation Trust last year. However, officials from the mental health trust said they had put in place actions to reduce the chances of similar tragedies happening again.

Mr Weatherley, who was first referred to mental health services in 1998, was admitted indefinitely to the Norvic Clinic secure unit in Norwich in August 2010 after pleading guilty to manslaughter on the grounds of diminished responsibility.

The killing of Mrs Weatherley came less than a year after his parents expressed concerns about the lack of support from the mental health care system.

The 36-year-old was admitted to St Clement's Hospital in Ipswich in October 1998 following three previous suicide attempts and he was diagnosed with schizophrenia after walking around the family home holding a breadknife because he thought people were coming to kill his family. He was admitted to a secure unit in September 1999 and again in January 2007 after trying to drown himself.

In April 2009 he was allocated a CMHT social worker and care coordinator, but on September 25 the care coordinator wrote to the patient's GP saying that he was being discharged as 'no further tasks could be identified.' Mr Weatherley had no contact from a health professional between September 25 and March 15 2010.

Dr Hadrian Ball, medical director of Norfolk and Suffolk NHS Foundation Trust, said the organisation had held a summit to review its response to the tragedy.

'We would like to stress again our sincere condolences to everybody affected by this tragedy and we can only hope this independent report will help answer any remaining questions about the sad events of March 2010. The report rightly points out a number of failings and also acknowledges major changes have been made in the way mental health services are run in the region.'

'We have improved the way patients are risk assessed and discharged and have trained 120 clinical supervisors. Their role will be to examine and challenge decisions about patient care and treatment.'

'Despite the many changes already made, we will study this report closely to ensure everything possible is done to learn from this tragedy. Each year we support 40,000 people with mental health problems across Norfolk and Suffolk and the vast majority live full and productive lives in the community. We will continue to do everything possible to improve our services and reduce the chances of such a tragedy happening again,' he said.

David Levy, regional medical director for NHS England, added: 'This report will help the whole of the NHS to learn the lessons and ensure services for patients are improved. Both NHS England and NSFT have taken this matter very seriously and we will work together to ensure that progress continues to be made.'