A 52-year-old man was stabbed to death in South Croydon last night.
Police arrested a 23-year-old man on suspicion of murder at the scene of the attack in Selsdon Park Road, near the junction with Pixton Way.
Police have said at this point of the investigation detectives are not actively seeking anyone else in connection with the murder and there is nothing to suggest at present that the victim and the suspect were known to one other.
Officers believe they know the identity of the 52-year-old, who was pronounced dead at the scene despite attempts by paramedics to resuscitate him.
Formal idenification has yet to take place but the man's next of kin have been informed.
A Metropolitan Police spokesman said officers were called to Selsdon Park Road at about 10.30pm on Thursday, April 24.
Police, the London Air Ambulance and London Ambulance Service paramedics attended the scene.
The spokesman added: "A 52-year-old man was pronounced dead at the scene.
"Officers believe they know his identity, but await formal identification. Next of kin have not been informed.
A post mortem-examination is due to take place this afternoon.
Police have closed Selsdon Park Road between Old Featherbed Lane and Farley Road while they continue their investigation.
Access to John Ruskin College, Gilbert Scott Primary and The Quest Academy is affected by the road closures.
The 23-year-old remains in custody in a south London police station.
Chief Superintendent David Musker, Croydon Borough Commander has released a statement following the attack.
He said: "This is a tragic incident and our thoughts, first and foremost, are with the victim's family and friends at this time.
"Whilst I cannot discuss any specific details due to the ongoing investigation, at this early stage detectives are not actively looking for any other suspects.
"Alongside the murder investigation, our priority is to reassure the local community in the area and we fully recognise the impact this incident will have on local people.
"I will be putting local neighbourhood officers out on additional patrols in and around the Selsdon area over the coming days.
"If you have any concerns, then please do not hesitate to speak to any of my officers that you see out and about, or call the local Selsdon and Ballards Safer Neighbourhoods Team."
Anyone with information that may assist police can call Crimestoppers on 0800 555 111.