The Ministry of Defence is considering six sites across London for the deployment of surface to air missle launchers during the Olympics.
The Lexington Building in Tower Hamlets and the Fred Wigg Tower in Waltham Forest have been identified as potential sites.
Also Blackheath Common and Oxleas Wood in South London, William Girling Reservoir in Enfield and Barn Hill in Epping Forest. Talks have already taken place with housing associations and residents. Organisers say it's to ensure a safe and secure Olympics.