A woman pedestrian was injured in a collison with a motorcyclist at the south end of London Bridge on Thursday morning.
The air ambulance landed shortly afterwards outside Oddbins causing the traffic junction at the top of Duke Street Hill to be closed.
City of London Police joined Met colleagues from Southwark in controlling traffic and crowds as commuters waited to photograph the helicopter taking off.
The aircraft left just before 9.15am rising above the Barrow Boy and Banker.
The victim is reported to be in a serious condition.
Traffic was also affected by an earlier accident in New Bridge Street at the north end of Blackfriars Bridge.