The young man who shot dead a police sergeant may never face charges because he is brain damaged and paralysed, a national newspaper has reported.

The murder of New Zealand-born Sgt Matt Ratana at the Windmill Road custody centre shocked the world and saw an outpouring of grief and tributes to the well liked and respected police officer from his colleagues and the community.

It has emerged that the prime suspect Louis De Zoysa hasn’t been interviewed because of the nature of the injuries he sustained during the incident where he fatally shot Sgt Ratana in the chest.

The 23-year-old’s family from Norbury are well known for their green lifestyle and when younger cycled together to their Thornton Heath school before the boys attended secondary school at John Fisher Roman Catholic comprehensive in Purley.

Neighbours said Louis, the eldest of five children, suffered with mental health issues and the BBC spoke to former schoolmates who said he watched violent videos at school and was obsessed with firearms.

Another said he was ‘brilliant’ at maths and could have gone to Oxbridge with his brother studying engineering at the University of Oxford.

His parents events manager Channa and Elizabeth, a translator and Green Party candidate in Norbury, even won an eco champions award and Mr De Zoysa ran Dr-a-bike repair sessions including two at Thornton Heath schools.

The bike sessions began at St James the Great where the De Zoysa children attended school ,when younger and all cycled to the Windsor Road site accompanied by Mrs De Zoysa riding an adult tricycle given to her by Cycling for All a Croydon project.

The popular rugby loving sergeant who was just months away from retiring after a 30 year career in the police was about to search the handcuffed suspect with a metal detector in a Covid screening cell when he produced a revolver that he had stuffed down his trousers.

Prince Charles described the senseless killing of Srgt Ratana as “heartbreaking” and “dreadful”.

Prime Minister Boris Johnson, Home Secretary Priti Patel and the Prime Minster of New Zealand Jacinda Ardern, where the officer was born, all added their condolences.

The commissioner, Cressida Dick described Sgt Ratana as a “talented police officer, a lovely man and highly respected by his colleagues”.