Several people have been stabbed in Streatham, south London, and a man has been shot dead by police, in what they describe as a "terrorist-related" incident.
Images on social media show a person face down on the ground outside Boots, with a police officer holding a gun next to a black BMW with emergency lights.
The person is wearing grey trousers, black shoes and a green jacket.
Sky's home affairs correspondent Mark White said photos appear to show the man wearing something resembling a suicide vest.
Metropolitan Police tweeted: "A man has been shot by armed officers in Stretham At this stage it is believed a number of people have been stabbed.
"The circumstances are being assessed; the incident has been declared as terrorist-related."