Bexley had the highest rate of serious child abuse incidents in England last year, new figures show.
Nationally, there has been an increase in the number of at-risk children being killed or seriously injured.
The National Society for the Prevention of Cruelty to Children said the figures must be a "catalyst" for the Government to urgently transform the child protection system.
Department for Education figures show 10 serious incidents regarding the welfare of children in Bexley were recorded in 2022-23 – up from one or two the year before.
Mid-year population estimates show 56,525 children lived in Bexley last year.
It means 17.7 incidents per 100,000 children were recorded in the area – the highest rate in the country.
A serious incident is when a child suspected of being neglected or abused has either been seriously harmed or has died.
It also includes any looked-after children who have been harmed or died, whether abuse or neglect is suspected or not.
Figures have been suppressed in areas where one or two incidents have been recorded to protect children's identities.
In England, 456 incidents were recorded – up marginally from 442 the year before, though this is still below a recent peak in 2020-21 of 536, which is substantially higher than any of the last five years.
The NSPCC said a child who has suffered serious harm or even died, often due to abuse and neglect by those who should protect them, is "behind every one of these figures".
Abigail Gill, associate head of policy, said: "It is babies and our youngest children who are most reliant on the adults around them for care and protection and particularly vulnerable to harm being inflicted on them."
Ms Gill added: "These stark figures must be a catalyst for Government to show the political will and leadership needed to transform the child protection system as a matter of urgency to protect our most vulnerable children."
Of the 456 incidents this year, 201 related to a child’s death, while 244 resulted in serious harm – which includes serious impairment of a child’s mental health or intellectual, emotional or social development, or serious impairment of their physical health.
The Department for Education spokesperson said: "Any incidents of abuse relating to children are abhorrent and we continuously work closely with agencies including Ofsted and local authorities to ensure strict protocols are in place to deal with cases quickly and effectively.
"Through our recently launched care strategy backed by £200 million, we are transforming the system to focus on more early support for families, reducing the need for crisis response at a later stage, alongside significant spending of £10.8 billion on social care this year alone, an increase of almost £800 million year on year."