An independent inquiry into the treatment of a paranoid schizophrenic with delusions about prominent politicians and the royal family has criticised mental health services.

The report identified six points on which opportunities to take an overview of the deterioration in the condition of Richard King were missed. He stabbed his mother-in-law's partner and was convicted of manslaughter on the grounds of diminished responsibility.

He had been in touch with the forerunner of Norfolk and Waveney Mental Health foundation trust for over a decade before the attack. Health and social care professionals had been concerned about his behaviour.

The report commissioned by the East of England strategic health authority found there were shortcomings in his care.

Chief executive Pat Holman said: "The trust has already made much progress, such as improving staff training and reporting procedures. We continue to review our improvement plan and draw into it recommendations made by the inquiry."