At least 17 people, including four children, were injured after a double decker bus crashed into a shop on a busy high street.
The bus smashed into a store front near on the junction of Harlesden High Street and Manor Park Road in Harlesden, north west London, at around 2pm.
Three people suffered serious injuries and were taken to hospital.
A London Ambulance Service spokesman said: "We treated 17 patients at the scene. We took three patients as a priority to hospital.
"A further nine adults and four children with minor injuries were also taken to hospital and one was treated and discharged at the scene."
London Fire Brigade station manager Sam Kazmanli said the building had been severely damaged and that people had been evacuated from the area.
The Metropolitan Police said no-one had suffered life-threatening injuries, while Transport for London (TfL) announced a full investigation would be launched into the incident.
Tony Akers, TfL's head of bus operations, said: "At around 2pm on Sunday 15 May, a route 18 double deck bus, operated by Metroline, was involved in a collision with a building on High Street Harlesden near the junction with Wendover Road, NW10.
"Emergency services attended the scene. There will be a full investigation into the incident."