Exclusions at Newham’s schools have increased by 81 per cent since 2013, as police chiefs have warned this could be contributing to a surge in knife crime.

Police commissioners from seven forces across England and Wales have written to prime minister Theresa May, calling for urgent action to fix the “broken” school system.

The letter – which was co-signed by London mayor Sadiq Khan – argues that exclusions put vulnerable children at risk of being sucked into violent crime.

In 2016-17, secondary schools in Newham handed out 1,740 exclusions to children, the latest Department for Education data shows.

This was a rate of eight exclusions for every 100 pupils, and an 81pc increase from 2013-14 when there were just 960 exclusions.

“Clearly, the way the education system deals with excluded young people is broken,” the police chiefs’ letter reads.

“It cannot be right that so many of those who have committed offences have been excluded from school or were outside of mainstream education.”

In Newham, there were 44 permanent and 1,696 temporary, or fixed-term, exclusions in 2016-17. The rise is not restricted to the borough, with the national exclusion rate rising by 44pc since 2013.

A spokesman for Newham Council said: “There has been a rising trend of exclusions nationally within secondary schools and within Newham this is partially due to better recording of exclusions.

“The council has recently given advice to schools about the exclusions pathway and work has begun on an improvement project.

“This will aim to reduce exclusions by improving early intervention and using managed moves from one school to another to give the opportunity for a fresh start.”

The National Association of Headteachers said it backed the majority of the police chiefs’ points, stating: “School budgets are at breaking point and many interventions for our most vulnerable young people are being cut.”

However, it added that violent crime was the result of “deep-seated problems” – including poverty, inequality, and cuts to police and council budgets – and could not be blamed on exclusions alone.

The letter to Mrs May also calls for off-rolling – where pupils are removed from the school roll without a formal exclusion – to be outlawed, and for greater funding for schools to improve early intervention for children at risk of exclusion.

The National Association of Headteachers said it backed the majority of the police chiefs’ points, stating: “School budgets are at breaking point and many interventions for our most vulnerable young people are being cut.”

However, it added that violent crime was the result of “deep-seated problems” – including poverty, inequality, and cuts to police and council budgets – and could not be blamed on exclusions alone.

Paul Whiteman, general secretary of the NAHT, added: “A school’s first duty is the safety of its students, and so school leaders need to retain the autonomy to exclude a violent pupil in order to keep everyone else safe.”

A Department for Education spokesman said permanent exclusions should only ever be a last resort.

He said: “It is still vital that young people who are excluded from school are able to engage with high-quality teaching and education.

“That’s why we have launched a £4 million fund which is delivering projects to improve outcomes for children in alternative provision, including pupil referral units.”

Ofsted said it had seen no convincing evidence that exclusions lead to knife crime or gang violence.