Staff shortages are leaving vulnerable children in Croydon waiting too long for assessment by social workers, inspectors have warned.

The rising number of children in care is also putting “increasing pressure” on health services, the council and the police, according to a report.

Ofsted, the Care Quality Commission, HM Inspectorate of Constabulary and HM Inspectorate of Probation examined in May how the borough’s public bodies tackle child protection.

“Significant improvement” is needed to cope with rising demand for services, concluded the resulting report, published last month.

The shortage of school nurses was particularly acute, inspectors found.

Croydon Health Services NHS Trust said filling the positions was “a challenge across the country, but especially in London”.

A spokesman added: “To address this, we have recruited more senior clinicians and have created development roles for nurses who will be trained in school nursing as part of their career progression in Croydon.

“We have also launched new training to ensure staff – both in our adult and children’s emergency departments – know when and how to refer to social services if a child is at risk, with oversight from the senior nurse in charge on every referral going out.”

Croydon Council currently cares for 830 children – more than any other London borough. Due to the Home Office’s screening unit in Lunar House, 433 of those are asylum-seekers.

A spokesman for Croydon Clinical Commissioning Group said: “New migrants to Croydon, including unaccompanied child asylum seekers, are part of our population from the moment they arrive and are one of the many factors that make up our unique population in Croydon.

“Midwives, health visitors, early learning practitioners, family nurses, children’s centres and voluntary and community organisations are working together to develop joint packages of care for families most in need of support, including those with safeguarding issues.

“Croydon’s GPs are being given specific training to support them in identifying and responding to the needs of our unaccompanied asylum-seeking children.”

A “very high” number of missing children in the borough is also placing further strain on police resources, according to the report.

Police in Croydon dealt with 174 missing persons reports in March alone.

Andy Tarrant, Croydon police’s borough commander, said: “Significant resources have to be devoted to dealing with missing young people, so we have a dedicated missing team which is a mix of uniformed officers and detectives.

“Croydon has the most looked-after children in London and there is a definite correlation between missing children and that volume, so it poses a lot of challenges.”

A council spokesman said: “We are pleased the report found there is a clear commitment from senior leaders in all agencies in Croydon to see children are kept safe, and the voluntary sector was found to be well-represented on the local children’s safeguarding board and that provision is making a real difference to the lives of children at most risk.”