The incident happened in Birkbeck Road near Clarence Road at around 6.20am today (July 23).
Officers and London Ambulance Service crews attended and found a person injured.
They were taken to hospital for treatment where their condition is unknown at this stage.
We have contacted Metropolitan Police for further information.
A spokesperson for London Ambulance Service said: “We were called at 6.20am today (23 July) to reports of a stabbing on Birkbeck Road, Sidcup.
“We sent resources to the scene, including an ambulance crew, an incident response officer and a paramedic in a fast response car.
“We treated a patient at the scene and took them to a local hospital as a priority.”
