The incident happened at Eltham Park South in Glenesk Road just after 8am today (April 7).
An ambulance crew, an advanced paramedic, a paramedic in a fast response car and an incident response officer from London Ambulance Service attended.
However, the person was pronounced dead shortly after.
We have contacted the Metropolitan Police for further information.
A spokesperson for London Ambulance Service said: “We were called at 8.02am today (7 April) to reports of a person unwell in Eltham Park, Eltham.
“We sent resources to the scene, including an ambulance crew, an advanced paramedic, a paramedic in a fast response car and an incident response officer.
“Sadly, despite our best efforts, a person was pronounced dead at the scene.”