Detectives in Croydon are appealing for witnesses and information following a stabbing in Drummond Road, Croydon.
Police were called at around 15:45hrs on Monday, 16 January to a report of a man stabbed.
Officers and London Ambulance Service attended and found an 18-year-old man in Charrington Road suffering from a single stab wound to the chest.
It is believed that the incident took place at around 15:30hrs near the car park in Drummond Road before the victim made his way to a shop in Tamworth Road for help.
He collapsed at the shop and was taken by friends to Charrington Road where he was found by police.
The man was taken by London Ambulance Service to a south-London hospital where he remains in a critical condition.
Detectives from Croydon CID are investigating.
There have been no arrests and enquiries into the incident continue.
Anyone with information is asked to contact police via 101 or @MetCC. Alternatively, contact Crimestoppers anonymously on 0800 555 111.