This is the terrifying moment a boy in school uniform ‘slashes’ woman with a knife in South Norwood.

The footage, which has already been viewed 843,000 times on Twitter, shows the youngster with a long-bladed weapon as the woman is on the ground.

An altercation broke out between the woman and a group of youngsters in Grosvenor Road.

The incident took place in front of a crowd of screaming children.

The woman attempts to swing at the youngster before being pushed over by another person in the crowd.

He appears to swing the knife at her four times before being guided away.

Police found the woman, aged in her 40s, with a slash wound.

Her injury was not believed to be life-threatening.

A boy, 15, was arrested on suspicion of grievous bodily harm (GBH).

He currently remains in police custody.

Police enquires are ongoing.

Detective Sergeant Danielle Power of south area command said: “We understand the concern that will spread through our communities in relation to this horribly violent incident.

“We would like to reassure parents and local residents that enhanced, highly visible patrols will take place at the end of the school day to reassure pupils, their parents and the wider community.

“We continue to work closely with the local school and to support the victim.

“We are aware of footage circulating on social media and ask that this is not shared further to avoid prejudicing any future legal proceedings."

Anyone who witnessed the incident is asked to call the police on 101 or tweet @MetCC and quote reference 5441/10May.

A spokesperson for the Met Police said: “Police were called at 4.35pm on Tuesday, 10 May to reports of an altercation between a woman and a group of youngsters at Grosvenor Road, SE25.

“Police and London Ambulance Service [LAS] attended.

“At the scene a woman, aged 40s, had suffered a slash wound. Her injury was not life threatening.

“A 15-year-old male was arrested on Tuesday, 10 May on suspicion of grievous bodily harm [GBH].

“He remains in custody at this time.

“Enquiries are ongoing.”

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