A Metropolitan Police spokesman added that at this early stage, it is believed the police vehicle had its 'blues and twos' in operation at the time of the collision.
The aftermath of the accident was posted on twitter by several eyewitnesses.
Two people had to be cut out of this car after it crashed with a police van in Bermondsey today. http://t.co/O28MuOrCdd
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An eyewitness said: "It was very unnerving. It was just after 12pm and there were suddenly police vans and cars everywhere."