The Mayor of London Boris Johnson said: "London is home to almost half of all people living with HIV in the UK, but a quarter of them are unaware they carry the virus.
"It is vital that people who might be at risk get tested, not only to reduce the risk of transmission to others, but to ensure they get the life-saving treatments that are available."
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A teenager has been airlifted to hospital after being stabbed outside a DLR station in south-east London.
By law, the Met Police has a duty to police public land outside grounds - that's costing them £9.3m a season.
John, who began running for Age UK back in the 1980s when he was aged 53, has raised an incredible amount since then - more than £40,000.