Attacks on NHS staff have risen during the past year

The button - in an ID card - would pinpoint a nurse's exact location using mobile phone technology.

It will also record the incident for use in future prosecutions.

The technology - along with specialist training of NHS staff on how to deal with violent situations - is being trialled at selected hospitals in the North West and South West.

In the last year there have been 116,000 incidents of members of the public using violence or aggression towards health staff.

The more assaults we see against GPs, the harder it will be for the NHS to recruit more GPs and retain their services Dr John Chisholm, British Medical Association

This represents an increase of 4,000 on the previous year's figures.

Health Secretary John Reid said: "Violence, harassment or intimidation against any NHS staff is utterly despicable and totally inexcusable.

"Nurses, doctors and other staff dedicate their lives to helping patients by offering pain relief to the sick or injured.

"Any violent behaviour - be it verbal or physical - is reprehensible.

"NHS staff should be confident that their workplace is safe and secure - especially during the holiday season."

Kidnap attempts

Sheelagh Brewer, employment relation adviser at the Royal College of Nursing said: "Far too many nurses are assaulted every year.

"This not only affects a nurse personally but the standard of patient care delivered in the NHS and morale at the NHS body involved."

Dr John Chisholm, chairman of the British Medical Association's family doctors committee, said: "The more assaults we see against GPs, the harder it will be for the NHS to recruit more GPs and retain their services.

"I hope that the launch of today's strategy will prove to be the catalyst for a reduction in the number of assaults on all NHS staff as well as the protection of NHS property."

Security at maternity and children's wards will also be stepped up in the wake of a number of kidnap attempts of babies from hospital wards.