Part of the roof of a four-storey block of flats is burning on Griffiths Road in Wimbledon. The fire brigade was first called around 9.54am, with teams from all over South and West London.
Three men have been taken to hospital by the London Ambulance Service.
Five fire engines are on hand, the London Fire Brigade said in a statement.
It is currently unknown what started the fire.
Footage of the scene shows the apartment building on fire under scaffolding, with gray smoke pouring out from under a plastic canopy.
More to follow…