Cops were called to five reports of knifings in Croydon between 6.56 pm and 9.12 pm resulting in two men being arrested, as the Sun reported.
One man was pronounced dead at the scene while two others have life-threatening injuries.
The Met said there was no information to suggest that all the incidents, which are still being investigated, were linked.
The first attack happened at 6.56 pm on Chapman Road which left one injured.
Around 20 minutes later, four men attended a local hospital - believed to be Croydon University Hospital - with "stab and slash" wounds, police said.
One of the men is fighting for his life.
At 8.08 pm, police were called to the scene of an attack on Wisbeach Road where one man died at the scene after paramedics desperately tried to save him.
Two others at the scene had stab wounds - although only one was taken to hospital.
Less than an hour later, at 8.51 pm, two more males presented themselves to a local hospital with stab wounds.
The final attack at 9.12 pm left one man injured on Dingwall Road. Police arrested one man and also cuffed the wounded male as well.
Detective Superintendent Nicky Arrowsmith said: "Sadly, tonight we have seen a number of needless and completely abhorrent violent altercations, including one that has tragically resulted in a loss of life.
Back on January 1, three people were injured in another stabbing incident that took place in London.
HJ/PR