Officers "took immediate action" on Friday following a tip-off through the new scheme, which lets parents, guardians and carers know if people with access to their youngsters have previous convictions for child sex offences.

Det Chief Insp Debbie Tedds said the arrest was linked to one of four calls received in week one of the 12-month Home Office trial.

She said: "Its was from a member of the public raising concern about a child. A man has been arrested and enquiries are ongoing. For operational reasons we cannot provide further details at this time."

She said agencies in the county were "not previously aware" of a risk to the child involved, or the circumstances.

WHAT DO YOU THINK OF THIS SCHEME?
Let us know
here

Further checks are being made in two cases - and a police force outside of the pilot area has been alerted as a direct result of another call.

Det Chief Insp Tedds added: "We will fully investigate every concern with our partners and, if disclosing information will increase the level of protection, we will share information with the main carer."

"We are really pleased at the response.

"Although it's still too early to get a real idea of the true level of take-up, we believe it has helped make raising concerns more visible and accessible to the public."

Under the new rules, parents and carers can check if those spending time alone with their children have been convicted of 87 offences under the Criminal Justice Act 2003.

Fears might be raised about babysitters, home tutors or a parent's new partner - the criteria is one of "significant unsupervised access" with an under-18.

Checks could take up to six weeks - but where a serious risk is identified police will take immediate action.

Details of convictions and cautions are given to the child's main carer or the person best placed to reduce any risk.

They are then obliged to keep their new knowledge secret - or could face prosecution themselves.

The scheme is being tested in four parts of the country and builds on existing arrangements for sharing information.

More information is available at www.warwickshire.police.uk/keepingchildrensafe

* To raise a concern, visit any police station, call the 24-hour hotline on 415899, send an email to keepingchildrensafe@warwickshire.police.uk or log on to www.warwickshire.police.uk