A 13-year-old boy has been arrested in Sheffield following social media posts encouraging schoolchildren to engage in violent behaviour.
The child is being held on suspicion of malicious communications, encouraging or assisting crime and an alleged public order offence.
It follows a national trend involving so-called 'red vs blue school wars' posted on social media.
On Friday, South Yorkshire Police said it was increasing patrols following the circulation of posts in the region.
In a statement on Facebook, the force warned about "a reckless attempt from mindless individuals to incite meaningless violence", although at the time it said there were no confirmed reports of criminal offences or injuries linked to the trend.
Following the arrest, Inspector Katie Hammond said officers had "been actively monitoring social media and carrying out intelligence checks, and doing all we can to track down the accounts responsible and shut them down".
"I believe the overwhelming majority of children here in South Yorkshire understand this trend is reckless and irresponsible, and not at all reflective of the real, positive relationships which exist between our educational establishments, young people and communities," Insp Hammond added in a statement.
The national trend, which first emerged in London last month, involved social media posts advertising so-called 'red vs blue school wars', encouraging confrontation between students from different schools.
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It prompted the Metropolitan Police to launch Operation Cedarfield, an initiative to tackle violent school gatherings across London.
On 1 March, the force confirmed officers arrested "two individuals in Central East London in connection with a recent trend of social media posts".
"Both suspects, a man aged in his 20s and a boy aged 15, were arrested on suspicion of encouraging or assisting in a crime," the statement added.
(c) Sky News 2026: Boy, 13, arrested in Sheffield over social media posts encouraging school violence
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