Officers from the British Transport Police rushed to Wembley Park station on Saturday night after reports of a medical emergency.
Members of Harrow Online sent images showing police cars and at least one ambulance outside the station shortly before 10:30pm.
A spokesperson for British Transport Police said: “Officers were called to Wembley Park Underground station at 10.20pm on Saturday 19 August to reports of a medical emergency.
“Officers attended alongside paramedics and a person was taken to hospital.”
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