A teenager suffering from a “serious head injury” was discovered collapsed by Rotherhithe Tunnel in the early hours of this morning.
Police were flagged down at 4.19am and found the 19-year-old collapsed at the south-side entrance to the tunnel.
An ambulance was called and the man was rushed to a central London hospital. The man remains in a critical condition.
Police believe they know the identity of the man and have informed next-of-kin.
Rotherhithe Tunnel was closed following the incident, leading to severe traffic problems in the surrounding area.
No arrests have been made and police enquiries continue. Anyone with information should call police on 101 or Crimestoppers anonymously on 0800 555 111.