'My son could so easily have been another Nottingham killer'

Shelly says Keith’s experience shows there has been a proliferation of “dreadful things happening with people with paranoid schizophrenia”.

She says: “If you were to see my son on the street, you’d think ‘bloody hell, that lads not right in the head’… but there’s a lack of knowledge from people and a total lack of support.”

“For this to keep happening, why are they not learning from these experiences? The bedrock of mental health is prevention and they’re not doing that anywhere near enough,” she added.

In a statement, Nottinghamshire Healthcare NHS Foundation Trust said it would not be appropriate to comment on individual cases.

Both Keith and Shelly have asked how the attacks could have been avoided

A Department of Health and Social Care spokesperson said: “Our thoughts remain with the families and friends of those who have been affected.

“All parts of the health system must work together to ensure those with mental health conditions get the help and support they need.”

Shelly believes it is imperative the trust learns from its mistakes. She is currently in the process of pursuing legal action against them in a bid to help other people.

“This has got to stop,” she said. “Stop it happening to other people. That’s what I want… some change, a black-and-white law saying if somebody’s ill, take it seriously.”