A formerly “outstanding” school for autistic children has been rated “inadequate” by Ofsted inspectors, who say school leaders are failing to safeguard pupils.

Ofsted published a report on Tuesday after visiting Meopham’s Helen Allison School in January without notice at the request of the Department for Education.

A summary of key findings said the school’s “safeguarding culture” was weak; that leaders “do not challenge each other to make the best decisions to keep pupils safe”, and that record-keeping and monitoring are poor.

The overall effectiveness of the school was judged to be “inadequate” as were key areas including effectiveness of leadership and management; personal development, behaviour and welfare; sixth-form provision; and overall experience of residential pupils.

Inspectors did find the quality of teaching, learning and assessment was “good”, as were outcomes for pupils.

But the overall picture was poor, with inspectors reporting: “Changes in leadership and teaching staff, together with a lack of oversight by the proprietor, have contributed to a sharp decline in many aspects of the school.

"As a result of this decline and concerns about safeguarding, there are now unmet independent school standards and unmet minimum standards for residential special schools.

“A growing number of staff are worried about the quality of leadership throughout the school, especially in terms of how leaders help them to manage challenging behaviour associated with pupils’ specific autistic spectrum conditions.

"Several staff and parents feel that leaders do not communicate well.

“A growing number of staff are worried about the quality of leadership throughout the school, especially in terms of how leaders help them to manage challenging behaviour associated with pupils’ specific autistic spectrum conditions..." - Ofsted

And it added: “Records show there have been instances where staff’s responses to challenging behaviours have been unsafe, unnecessary and inappropriate, including in the residential provision. These practices are not in accordance with either government guidance or the school’s internal policies or procedures.”

Kirstie Fulthorpe, director of education for the National Autistic Society, which runs the school, said: “Everyone involved in the school is deeply disappointed that we’ve fallen short of the high standards we, our students and their families expect.

“The safety of our children and young people has to be the foundation of everything we do. But, as the report highlights, there were unacceptable weaknesses in the school’s safeguarding systems and processes.

"We kept children safe, but inadequate recording and reporting meant that we weren’t doing everything we should have been to reduce the risk that they might come to harm.

“Despite identifying many strengths regarding the pupils’ learning, progress and our curriculum offer, these weaknesses meant the school is currently judged to be inadequate.

“We took immediate action to start addressing the concerns raised by Ofsted and make sure there is a strong culture of safeguarding for everyone at the school.

"This included reviewing and updating all our systems and processes.

"We always want to be as open as possible and reached out to the parents, carers and students as soon as we could to explain what we’re doing to improve.

“We have a strong community of staff, students and their families at the school.

"Together, we are determined to make sure we are a great school.”

The Helen Allison School currently has 81 pupils on roll, three of whom are residents.

Inspectors had last visited in November 2016.