Police say the victim was cycling across the pedestrian crossing outside Brixton Tube station when he was hit by a dark or black car.
We need to locate the car involved and speak to the driver as soon as possible. The victim was left lying in the road having suffered very serious injuries.
I would urge anyone who witnessed the collision or has any information, regarding the identity of the driver or whereabouts of the car to contact the Hampton Traffic Unit on 020 8941 9011 or Crimestoppers anonymously on 0800 555 111.
More top news
Hertfordshire based eBay seller relists ad for the car that "ruined her life" after the auction website deleted it for swearing.
The accident happened on Clapham Road at lunchtime.
Tower Hamlets tops the league, with the population set to soar 25% by mid-2024.