Two people have been stabbed during an “incident” at Sony Music’s headquarters in central London.
Firearms officers and paramedics were called to the building in Derry Street, Kensington at about 11:00 GMT. An arrest was later made.
People were evacuated from the building and roads nearby were closed.
The Met said there was no evidence of any firearms involved and it was not being treated as terror related.
London Ambulance Service said paramedics had taken one person to a major trauma centre and another was taken to hospital.
Neither of those stabbed suffered life-threatening injuries, Scotland Yard said.
Evacuations had taken place “as a precaution” and officers remain at the scene, they added.