BBC news has a lot of information.
One interesting technology part – again from the BBC
Mobile phone services across London were jammed with all major networks reporting problems as people tried to contact relatives and friends. A spokeswoman for Vodafone said the emergency services were being given priority.
Was ACCess Overload Control (ACCOLC) put in place?
More details here, here and here.
Year 2000 ACCOLC article here.