An 18-year-old man has been arrested on suspicion of murdering Leonne Weeks, 16, who was found dead on a path in Rotherham.
London Shopping Sites Threatened In Video
A video claiming to be by Somalia's al-Qaida-linked rebels has urged Muslims to attack London shopping sites including Oxford Street and Westfield Stratford City.
The extremist group al-Shabab are behind the attack on a shopping mall in Kenya in 2013, in which 67 were killed.
A masked narrator in the 76-minute clip warns of more attacks in Kenya and calls on Muslims to attack shopping centres, specifically mentioning Oxford Street and the Westfield centre.
He also listed shopping malls in America and Canada as potential targets.
Security has reportedly been increased at the sites in the US and Canada but the Met Police said it does not comment on security.
A Met spokesman said: "The MPS Counter Terrorism Command is aware of the video and is assessing the content.
"We remind the public that downloading extremist material may constitute an offence."
The authenticity of the video could not be verified.
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