Prolific offenders and paedophiles are to be monitored by new satellite technology under three pilot schemes beginning on Thursday.
The tracking device will be monitored by a control station
It is the first time a European country has used satellites to monitor the movements of offenders.
Convicted burglars, robbers and car thieves will be fitted with an electronic device that can be tracked by satellites 24 hours a day.
The trials are in Greater Manchester, West Midlands and Hampshire.
The electronic device will be monitored by a control station that records the location of the offender to within a few metres using global positioning system (GPS) technology.
If the offender strays into an area they are excluded from the police are alerted.
The system will also be used to prevent sex offenders going to playgrounds and schools and to stop people convicted of domestic violence from approaching their victims.
Offenders will be required to wear the device as part of a community sentence, or as a condition of their release from prison.
Initially, the system will be used to track up to 120 offenders at any one time, but if the technology works, the Home Office will massively expand it in England and Wales.
Home Secretary David Blunkett launched the trials in Greater Manchester on Thursday.
He calls the scheme a "prison without bars".
Speaking at the launch, he said the system would help to ensure offenders are "sticking to the conditions of their
licence and staying away from crime".
He said: "Our sentencing reforms were not just about being tougher on the most serious offenders.
"This technology will allow us to develop and promote the tough community sentences which are vital if we are to prevent re-offending and give non-violent offenders a chance to serve an effective sentence in the community."
Correctional services minister Paul Goggins told BBC Radio 4's Today programme that it could cover several thousand people, including 5,000 prolific offenders.
He said: "We estimate there are 5,000 prolific offenders causing major problems and mayhem with their offending behaviour, day in, day out. So they would be a clear target.
"It will be a very, very clear, constant reminder to the offenders that
we're watching them, we know where they've been, we know what they're doing and if they stray, we'll act to stop them."
Harry Fletcher, assistant general secretary of probation union Napo, said the system was a "very expensive resource" only suitable for the most serious criminals.
"Satellite tracking is another form of control which by itself will not prevent crime. It must be seen as part of a package," he said.
'No major complaints'
Ex-prisoners' campaign group Unlock favours the tagging system as an alternative to jailing offenders.
Unlock's chief executive Bobby Cummines said: "I welcome this with open arms.
"I welcome anything where we can monitor people in the community instead of throwing them into prison."
Mr Cummines said tagging systems allow families to stay together, which is the key to rehabilitation.
Human rights group Liberty also said they had "no major complaints" with the system.
The electronic tagging which the government currently relies on is only able to set off an alarm when the offender breaches a curfew.
If a criminal walks out of the house after their curfew an alarm will sound at a central control room, where operators then notify police.
However, under this system there is no way of knowing where the criminal has gone.
1: Offender wears tracker device on belt, with wireless connection to ankle tag.
2: Belt device tracks own location using GPS satellite signals.
3: Location data transferred from belt device to telephone network.
4: Data sent to control centre, which can be specifically alerted if offender enters exclusion zone or breaks other conditions. Radio frequency alarm also sent if tracker and ankle tag are separated.
5: Offender's position shown as location trails on computer map.