The first incident took place in Rushey Green where a man in his 20s was found injured just after 3am today (October 15).
He was taken to hospital for further treatment but died shortly after.
His next of kin have been informed and are being supported by specialist officers.
No arrests have been made.
Borough Commander Trevor Lawry, who leads policing in Lewisham said: “Our thoughts go out to the family and friends of this young man who have lost someone they love in such a tragic way.
“I know the community will have concerns following this incident, a dedicated homicide team is currently working to piece together this morning’s events.
“If you have any information for police, please do come forward.
“A crime scene will be in place for several hours as part of the investigation, and I thank local residents for their patience.”
Shortly after at around 8am, emergency services were called to reports of a stabbing in Farley Mews near Mountsfield Park.
A man was treated at the scene and rushed to hospital where his condition is unknown at this stage.
It is also unclear at this time whether these two incidents are linked.
We have contacted the Metropolitan Police to clarify whether these two are linked.
