The number of autistic children being excluded from schools in Wirral has shot up, amid warnings that vulnerable students are being "failed" by the education system across England.

Data from the Department for Education has revealed that 33 children with Autistic Spectrum Disorder as their primary special educational need were excluded from primary, secondary and special schools in Wirral in the 2015/2016 academic year - the last year for which data is available - up from 20 in 2011/2012.

Of the children excluded in 2015/16, one was permanently excluded while 32 were given one or more temporary suspensions, known as fixed-period exclusions.

The figures - which were obtained through a Freedom of Information request submitted by the charity Ambitious About Autism for every local authority in England - showed there was a disparity between the rate of exclusions for autistic children and for the overall school population.

In the case of pupils with autism, 4.4% were given at least one exclusion in 2015/16, compared to just 2.2 % of the wider population.

Exclusions were also up across the school population as a whole, but by a far smaller margin than in the case of autistic pupils alone - 8.4%.

This too was the case for pupils with special educational needs (SEN) more generally, for whom exclusions rose by 1.7 %.

According to Ambitious About Autism, the fact that the rise in exclusions for SEN pupils overall was not as high as that for autistic children specifically shows children are being excluded simply "because they are children with autism".

It is unlawful in England for schools to exclude pupils on the basis that they have additional needs or a disability that they are unable to meet.

According to Ambitious About Autism, exclusions can cause mental health problems for children with Autistic Spectrum Disorder, as well as having an impact on their attainment at school.

Chief Executive Jolanta Lasota said: "Schools are shutting out thousands of children with autism.

"The impact of these exclusions cannot be underestimated - not only do children fall behind academically, but the isolation from their peers creates deep unhappiness, social anxiety and mental health problems."

Across England, the number of autistic children being excluded increased by almost 60%, rising from 2,825 in 2011/12 to 4,490 in 2015/16, while the number being permanently excluded more than doubled.

Every region saw an increase of at least 45% , while more than a third of local authorities saw a rise in the number of children with autism being excluded despite a drop in overall exclusions.

Ambitious About Autism has also warned that many more instances are likely to go unrecorded, with schools known to sometimes informally exclude autistic pupils by sending them home to "cool off", despite it being unlawful.

The charity said that better training was needed to combat widespread "misunderstanding" of exclusion law among teachers, while suggesting that pressure on funding could also be part of the problem.

A spokeswoman from the Department for Education said that government guidance was clear that "unofficial exclusions" were unlawful, regardless of whether parents consented to the arrangement.

She also said that the department had launched a review of school exclusions.

"We want every child with autism to have the support they need to unlock their potential, no matter what challenges they face," she continued.

"Thanks to this Government's reforms, more children and young people with special educational needs and disabilities are getting the support they need at school and college, and the number who move on to training schemes, apprenticeships or supported internships is increasing.

"We know more needs to be done to make sure that vulnerable children are not unfairly treated.

"The review aims to explore how school use exclusions overall and in particular why some groups of children such as children with autism are more likely to be excluded than others."