A 29-year-old man has been arrested following a stabbing incident on Marsham Street in Westminster.
An injured man in his 60s entered the Home Office for help after the "unprovoked" attack.
Police say the victim's injuries were not life-threatening nor life changing.
London Ambulance Service said he was taken to a major trauma centre.
Two eyewitnesses described what they saw.
Report by Jonesia.
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