Mental health patients in West Norfolk who need acute treatment face being sent to Norwich or further for a hospital bed after bosses closed the last remaining unit to new admissions.

The decision, by Norfolk and Suffolk NHS Foundation Trust, was taken because of a lack of staff available, chief executive Michael Scott said.

There are 20 inpatient beds at the Fermoy Unit, of which 15 are currently occupied by patients.

Those patients will not be moved and only discharged when they are ready, but there will be no further admissions.

New patients will instead be treated at Hellesdon Hospital, Norwich, Northgate Hospital, Great Yarmouth, or at Mundesley Hospital, in Gimmingham.

Mr Scott said the closure was temporary, but campaigners warned it would result in more mental health staff leaving.

The Fermoy Unit is situated on the Queen Elizabeth Hospital site, near King's Lynn.

In January NSFT said it could not rule out closing the unit.

That prompted North West MP, Sir Henry Bellingham, to say it would be completely unacceptable if the area was left without mental-health beds.

Last night Mr Scott said: 'This temporary measure is to ensure the safety of our patients and staff.

'This is a short term plan while we continue to recruit new staff to ensure we maintain safe staffing levels.'

He said hiring agency mental health staff had proved difficult in West Norfolk, and added the trust will continue to review and manage the situation at Fermoy on a day to day basis.

'We are working closely with West Norfolk Clinical Commissioning Group to look at a number of long-term options for the unit,' he said.

'We have an enhanced recruitment programme underway and are actively looking for additional staff across both Norfolk and Suffolk.'

But a spokesman for Save Mental Health Services in Norfolk and Suffolk described the situation as a 'tragic farce', and said it was a result of decades of under-investment in mental health.

'The people of Norfolk and Suffolk can't afford to lose another 20 acute psychiatric inpatient beds,' the spokesman said.

'Talk of staff shortages, building issues and temporary closure are the same excuses used previously to close vital wards.'

The spokesman said the trust was paying the price of making many staff redundant during the organisation's redesign during 2012-13.

Have you got a mental health story? Email nicholas.carding@archant.co.uk