A human rights group has warned an advanced CCTV surveillance system being developed for the London 2012 Olympics would not be legal.

The DYVINE system would allow a central police control room to remotely tap-in to any CCTV network in London and plot the information on a detailed 3D map.

Defence company EADS, which is developing the system, hopes it will provide a key policing tool in what some have described as Britain's greatest peace-time security challenge.

Number-plate recognition cameras as well as private networks, like those of a shopping centre or car park, would all be accessible to allow authorities to track suspects throughout the capital.

Advanced computer intelligence systems would assist officers by filtering out all but the most relevant CCTV feeds coming into the control room.

This would reduce time normally spent scrambling from one camera to the next.

Speaking to Sky News, Richard Fletcher, Senior Security Advisor at EADS, said the system's main role was to provide the control room with the most relevant information available.

"In an urban environment there are a lot of cameras, but they're not all linked in, and they're all on single feeds, so you are overwhelmed with information," he said.

"In this situation the system would clearly be very valuable."

But human rights group Liberty has warned that, as the law currently stands, such a system would not be legal.

Spokeswoman Isabella Sankey said: "Effectively somebody can be monitored 24-hours-a-day as they go about their business, so this is a fundamental shift in what CCTV can do."

She added: "That's why we are calling for legislation and a public debate before anything like this goes forward."

The Home Office said: "The Government is committed to ensuring a safe and secure London 2012 Olympic and Paralympics Games. Our plan for security has already been circulated to key stakeholders.

"We are now in the process of developing this further, integrating it with the security detail developed by the Olympic Delivery Authority and the London Organising Committee for the Olympic Games."

The draft Security Strategy for the Games will be presented to ministers next month.

Responsibility for planning of the Olympic Security will then be moved from the Home Office to the Office of Security and Counter Terrorism.