Hundreds of people were evacuated from tourist boats on the River Thames after a passenger ferry collided with a barge carrying rubbish near the iconic OXO Tower.
A number of people on board the City Cruises vessel were hurt - including at least three with neck injuries - following the crash at around 2.15pm opposite the Oxo Tower, near Blackfriars Bridge, in central London, British media report.
A fleet of ambulances were lined up on South Bank ready to take casualties to hospital and several River Police vessels were at the scene.
The City Cruises vessel was visibly damaged but did not appear to be sinking.
Some of the passengers on board the stricken passenger ferry were being transferred to other boats as a full-scale rescue operation swung into action.
Steve King, duty helmsman said: 'There was quite severe damage to the front. A couple of windows were smashed and there was glass everywhere.
Mr King said there were 362 passengers on board at the time.
A spokeswoman for City Cruises said: 'Today at 14:25 the Millennium Time - part of City Cruises' sightseeing fleet - made contact with a commercial vessel while sailing by Coin Street on the River Thames.
'Seven minor injuries have been reported, none of whom were hospitalised.
'All other passengers were guided off the boat promptly by City Cruises, who continue to do everything they can to support the authorities and those involved in the incident.
Safety on the Thames was overhauled in the wake of the Marchioness disaster in 1989, which saw 51 people die when the pleasure cruiser hit a dredger.