A record number of children are being excluded for racist bullying, a Guardian analysis has found, prompting calls for an urgent government intervention to tackle bigotry and prejudice in schools across Britain.

Last year, 4,590 cases of racial abuse among school students were deemed serious enough to warrant fixed or permanent exclusion, up from 4,085 in the previous year.

The increase of more than 500 is the highest leap in a decade, after remaining relatively stable since 2008-9, when the figure was 3,950. The number is rising at a faster rate than student population growth. The findings were echoed by data separately obtained by the Guardian in a snapshot of 39 local authorities which shows a similar rise in racist incidents, surging from 2,694 to 3,651 in three years.

The data comes days after a disturbing video of a Syrian refugee being attacked in the grounds of a UK school went viral, prompting widespread condemnation. In the video, a 15-year-old Syrian boy is taunted and pushed to the ground, as other students look on. A teenage boy is to be charged with assault after the video emerged.

Teachers, charities and MPs expressed concern about the “deeply troubling” picture that they said the data showed in schools, and called for the Department for Education and Ofsted to intervene.

Experts put the surge in racist incidents down to increased hate crimes and bigotry in society at large, with some also pointing to the decision made during the coalition government to remove a duty on schools to monitor the incidence of racist bullying. However, others said the spike could be due to a zero-tolerance approach to racism.

Chris Keates, the general secretary of the National Association of Schoolmasters Union of Women Teachers said the rise in exclusions was “disturbing”, although they showed unacceptable behaviour is being seriously challenged by schools. “[Our] own research shows that overt and covert instances of racism are a daily fact of life for far too many black and minority ethnic pupils and teachers,” she said.

The Labour MP David Lammy said the figures were a reflection of the government’s attitude and treatment of migrants. “The government’s hostile environment is driving migrants to overdoses, suicide attempts, fainting and chest pain … We need to radically reform our immigration system in a way that is just and humane,” he said.

Lola Okolosie, an English teacher, echoed Lammy saying the figures were not surprising “given that in the last decade we have had such toxic rhetoric surrounding immigration and migrants”.

She added: “Young people are merely reflecting the prevailing climate … Schools need to not pretend the problem does not exist. Senior leadership teams themselves need to consider their own unconscious biases as they are often all white teams with a very basic understanding of what constitutes racism. Ultimately though, this is not an issue that can be fixed by schools when the larger cultural discourse is one which seems immigrants as a burden.”

The figures mirror the charity Childline’s figures, which show children as young as 9 are contacting Childline about race or faith-based bullying. There have been more than 2,500 counselling sessions in the last three years about racial and faith-based bullying. Muslim, Jewish, Christian, Black and Sikh children were among those who have contacted Childline about the issue.

Another dataset obtained by the Guardian shows that the number of racist incidents in primary and secondary schools has risen sharply in three years. Freedom of information figures from 39 local authority areas shows a rise from 2,702 incidents in 2014 to 3,660 in 2017. In Glasgow the number of reports for racist bullying in local authority-run schools went from 35 to 195 across that time period. A Glasgow city council spokeswoman said: “There is no place for racism in Glasgow and our schools take a zero-tolerance approach to any form of bullying incidents.”

In Rochdale, the number of reports doubled, surging from 215 to 407. Primary school aged children accounted for 145 incidents, up from 64. The majority of perpetrators were male by more than three to one. The council said racist incidents are taken very seriously and they are dealt with robustly. “We are seeing improved data returns from schools (from 78.5% to 99.6% completed) which explains the increased figures,” they said.

Schools used to have a duty to monitor racist bullying but the coalition government under David Cameron removed this obligation, which the anti-racism charity the Runnymede Trust said, “buried the problem rather than addressing it”.

Zubaida Haque, the deputy director at the trust said: “It is hugely important that the Department of Education and Ofsted intervene on this issue soon. Teachers have told the Runnymede Trust that they do not feel equipped to address the growing prejudice and racism in schools, which by the way is also directed at them. Schools need to be discussing issues about racism, intolerance, identity, migration and our colonial history more openly and urgently. Children should not feel isolated.”

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Her words were echoed by Lauren Seager-Smith, chief executive at the anti-bullying charity Kidscape, who said: “We are deeply troubled to see the rise in racist incidents involving children and young people, and this reflects growing concern that Kidscape and other charities in the anti-bullying sector have had for some time.”

“Under Labour we had separate guidance for schools on racist bullying and a strategic approach to community cohesion, but this guidance was removed and schools are now left to find their own way, with very little accountability beyond occasional questions asked by Ofsted inspectors,” she added.

“We are calling for mandatory teacher training on all forms of bullying and harassment including race and faith targeted bullying and for much higher levels of accountability at a local level. We also believe that every racist incident should give rise to close inspection of what is happening at a peer and school-based level.”

A DfE spokesperson said: “Bullying of any kind is completely unacceptable and abhorrent in any setting including schools.”

Referring to the overall picture rather than the data on racist bullying, they added: “While we know there has been an increase in exclusions, there are still fewer than a decade ago. We have launched an external review, led by Edward Timpson, to look at how exclusions are used and why certain groups are disproportionately affected.”

In the UK, Samaritans can be contacted on 116 123 or email jo@samaritans.org. In the US, the National Suicide Prevention Lifeline is 1-800-273-8255. In Australia, the crisis support service Lifeline is 13 11 14. Other international suicide helplines can be found at www.befrienders.org.