Detective Superintendent Helen Millichap of Newham Police described the attack on the 16 year-old as "really unusual". She hopes the attacker will quickly be identified.
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Sixth form students in Bexley are teaching younger pupils about potential dangers online and how to use social media safely.
London singer-songwriter Dua Lipa and Croydon grime artist Stormzy led the charge at the Brit Awards, winning two prizes each.
Stormzy used his Brit Awards performance to launch an attack of Theresa May and her Government over the Grenfell Tower tragedy.