Police were called at 15:45hrs on Sunday, 8 September to reports of suspicious activity in Sydenham Road, SE29.
Officers attended. Shots were subsequently heard and firearms officers were also called to the scene along with the London Ambulance Service.
A man in his 20s was found with gunshot wounds. He died at the scene at 15:50hrs.
Police remain at the scene – there have been no arrests at this stage and enquiries in to the circumstances continue.
Anyone with information about the incident is asked to call police 101 quoting CAD 4860/8Sept or the independent charity Crimestoppers on 0800 555 111. They do not ask your name and cannot trace your call or I.P address.