Watchdogs have returned to Norfolk County Council to investigate whether the authority has improved the way it protects and looks after the county's most vulnerable children.

Inspectors from Ofsted have started a four-week visit to the county to check up on progress in the wake of two highly critical reports into children's services at County Hall.

The 2013 reports found that child protection services and services for looked after children were inadequate.

Under pressure from MPs, department director Lisa Christensen resigned and interim director Sheila Lock was appointed last year.

Experienced troubleshooter Mark Gurrey has also been drafted in to help oversee the council's attempts to turn the department around.

And, last month, a new permanent director, Michael Rosen, was appointed, although Ms Lock has stayed on for a few more months.

Asked earlier this year whether an Oftsed verdict of 'requires improvement' would be seen as a failure, Ms Lock said: 'I think it's likely that further work will be required – if you look nationally authorities that have been inadequate in just one area have taken three years to turn it around.

'Most authorities haven't come out of inadequate and gone straight to good – they have gone into requiring improvement, which is the step in between.

'I think, therefore given the scale of the task here, getting requires improvement would be a real positive – so no I would not see it as a failure, just a step on the journey.'

The team, consisting of up to 10 inspectors, will be carrying out audits and interviews across the county from next week, completing the work at the end of the month.

One of the key issues the inspectors identified last time around was a lack of strategy over early help and improving that service has been a major plank of Ms Lock's work. The number of children in care - 1,057 - is the lowest level since October 2012.

But there has been controversy. In May, a team manager in children's services was dismissed after a probe into his actions.

Peter Barron had been suspended since December, but, following an independent investigation and disciplinary hearing, the council told him in January that he was facing dismissal.

While Norfolk County Council refused to discuss the circumstances, it is understood to relate to a recommendation Mr Barron made to remove a child from a foster carer – in which he made statements which appeared not to be backed up by evidence.

An independent review is also under way into the treatment of Norfolk's foster carers, with the former chief executive of Middlesbrough Council, Ian Parker, at the helm.

A third Ofsted report in 2013 also criticised the council's effectiveness at supporting school improvement, although that was deemed 'effective' after a return visit a year later.

In March, children's minister Edward Timpson wrote to the council following a Department for Education review into progress and said the findings were 'encouraging,' with officials 'pleased by the clear signs of progress in a range of areas'.

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