A spokesman for air traffic control company Nats said:
Just before 8am today a helicopter crashed in central London close to Vauxhall Bridge.
Earlier in the helicopter's journey the pilot had been receiving an air traffic control service from Nats, although was not receiving a service at the time of the crash.
The incident will be subject to an investigation by the Air Accidents Investigation Branch and Nats will assist any inquiry.
Two men were killed after a helicopter collided with a high-rise crane in London and plunged more than 700 ft to the streets below.
The pilot of the helicopter which crashed had thousands of hours of flying experience including for films such as Die Another Day.