The Police Central E-crime Unit will aim to tackle online frauds including lottery scams, banking swindles and attacks on corporate networks.

With about 45 officers and a £4.5 million budget, the unit will help co-ordinate the response across England and Wales to computer-based crime.

It will include a specialist response unit of highly-skilled officers who will respond to attacks on the national electronic infrastructure and businesses.

Senior officers hope the central unit will be more effective in the fight against complex and elusive electronic scams, often based overseas.

Commander Sue Wilkinson, of the Metropolitan Police, said it will be composed of a mixture of police officers, analysts, academics and IT specialists.

She said: "It is a completely different picture of crime to what we have dealt with before. E-crime is borderless.

"The chances are that any one e-crime will not just cross local or national borders, but international borders too. Our conventional policing structures and crime investigation policies do not really apply to this new type of crime.

"However, much of the time it is traditional types of crime spreading through a new system. All sorts of different types of crime are being perpetrated."

The National High-tech Crime Unit, which was absorbed by the Serious Organised Crime Agency on its formation in 2006, will continue to operate.