An individual has been taken to hospital with "life-changing injuries" after an incident at St John's Wood Tube station on Thursday morning.
British Transport Police (BTP) and the London Fire Brigade were both in attendance after being called to reports of a "casualty on the track".
The incident is not being treated as suspicious.
A BTP spokesperson said: "Officers were called to the scene at St John’s Wood Underground station at around 7.40am on Thursday May 27 following reports of a casualty on the tracks.
"Paramedics attended the scene and a person was taken to hospital where they are receiving treatment for injuries which are believed to be life-changing."
The Jubilee Line was suspended, and by mid-morning was reporting "severe delays due to an earlier customer incident".
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