The head of Ofsted, Sir Michael Wilshaw, has criticised police forces in England for failing to take child protection matters seriously.
He said that a failure to change could lead to further cases of child abuse like the ones in Rotherham and Oxford.
Sir Michael said police forces were not sharing information “in a timely way” and were not informing social workers quickly when children went missing.
His criticisms were made in a letter to the chief inspector of constabulary.
In response, Sir Thomas Winsor said he would work to ensure officers fully understood their duties on safeguarding children.
In his letter to Sir Thomas, Sir Michael said there were cases where police officers had failed to attend key meetings about child protection or visits with social workers.
In a number of forces there were delays in flagging up domestic abuse cases to the local council.
He said the “most serious concerns” were raised about Cleveland Police’s support for children’s services in Stockton-on-Tees.
In one case, an Ofsted inspector questioned a police decision to close a case even though “there was clear evidence that the children concerned had suffered non-accidental injuries”.
Sir Michael said: “I am writing to alert you [Sir Thomas] to my growing concerns about the failure of some police forces to take their child protection responsibilities seriously.”
He said he would “like to be reassured that every chief constable recognises the vital role that the police have to play in protecting our most vulnerable children”.
“They are the ones armed with the intelligence to identify where organised abuse may be taking place and to spot emerging patterns of criminal activity.”
He went on: “My worry is that if chief constables fail to give this issue sufficient priority, we may see a repeat of the sort of catastrophic failings we saw a few years ago in places like Rotherham, Oxford and elsewhere.”
A report found that in Rotherham, 1,400 children were systematically sexually abused between 1997 and 2013, while in Oxford more than 300 were abused and tortured over a period of more than 15 years.
In a written response to Sir Michael, Sir Thomas said he was currently assessing how effectively police forces investigated offences involving vulnerable victims and how they worked with other agencies to keep children safe.
Sir Thomas said forces were also running a rolling programme of child protection inspections.
He wrote: “These inspections provide a very thorough assessment of how well a force handles child protection matters, including, but not limited to: how well officers understand and respond to vulnerability and risk; how well forces deal with missing and absent children; online abuse and online child sexual exploitation; children in custody; and the management of registered sex offenders.”
He continued: “We will persist in ensuring that the police understand their very high public duty most efficiently and effectively to use their powers, and discharge their responsibilities, in connection with the protection of children.”
Temporary Deputy Chief Constable Simon Nickless from Cleveland Police said: “Cleveland Police takes safeguarding extremely seriously and works closely with all local authorities and other safeguarding agencies on a daily basis to protect children from harm.”