London fire brigade and paramedics have attended the scene as well as the British Transport Police, who are now working to identify family members of the deceased.
TFL confirmed on Twitter the site was closed due to a “customer incident”
The operator has since suspended the Bakerloo line with no service between Paddington and Elephant and Castle, causing minor delays along the rest of the line.
A police spokesperson said: "Officers were called to Oxford Circus station at 4.20pm today following reports of a casualty on the tracks.
"Paramedics also attended however sadly a person has been pronounced dead at the scene. Officers are now working to identify the person and inform their family.
"The incident is not being treated as suspicious and a file will be prepared for the coroner."
A London Ambulance Service spokesperson added: "We were called at 4.21pm today (9 March) to reports of a person injured by a train at Oxford Circus Underground Station.
"We sent an ambulance crew and an incident response officer. We also dispatched London's Air Ambulance.
"Sadly the patient died at the scene."
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