The Civil Contingencies Bill will seek to modernise Britain’s response to national emergencies by protecting the country from attacks on the infrastructure including the “electronic network” and the water, electricity and telephone systems.

Airlines, the transport network, town halls and the postal service could also come under police direction in the event of a national disaster.

The bill, to be unveiled by Douglas Alexander, a senior Cabinet Office minister, this Thursday will give ministers powers to issue orders to internet service providers and those utilities that rely on the web.

It will also lay down new rules to ensure that all local authorities have audited plans to deal with potential threats.

Senior officers will have powers to enlist any member of the public to help civil defence staff. They will be able to commandeer equipment and buildings, for which the owners will receive financial compensation.

However, in a move designed to allay fears that the bill could pave the way for regional police states, ministers have decided against giving the police powers to run the BBC.

The police already have extensive authority to control some parts of the national infrastructure and order rapid evacuation of large areas, such as city centres.

But ministers say the existing 1920 Emergency Powers Act is out of date. “The bill will recognise the new scale of threat by widening the definition of what an emergency is,” said one Whitehall source. “We are concerned that people might try to target the City or the information network and the internet.

“A serious attack to stop information being circulated through the internet and electronic highway was not envisaged by the original act. The new bill will allow police to take on special legislative measures to deal with the threat.”

A draft version of the bill proposes that ministers will be able to invoke regional or local states of emergency with any situation that “causes or may cause serious harm to the welfare of the public”.

These range from an accident involving motor traffic, flooding or an environmental disaster to a biological, chemical or nuclear dirty bomb attack.

Officials yesterday played down the suggestion that the bill would give police draconian new powers but pointed out it would allow the powers to be used in wider areas.

“The bill is about timely modernisation, about bringing things up to the 21st century,” said one insider. “Computer networks, water, electricity and gas utilities could all be targets and obviously that has big knock-on effects.

“The more we get information online, the more people have broadband, the more that hospitals and electricity generators rely on the internet and electronic information.”

Firemen as well as police will be able to cordon off streets to remove or contain people in the event of a major terrorist attack.

Those impeding a police officer or civil contingency force soldier will face big fines or could be restrained by force.