Shocking findings by care regulators, the Care Quality Commission (CQC), revealed that 23 per cent of care homes, nursing homes and home care services require safety improvements, with a further two per cent found to be inadequate.

One in three nursing homes, responsible for the care of people with the highest level of need, are failing on safety.

Issues witnessed on surprise visits by inspectors found medicines being administered unsafely, alarm calls going unanswered and residents not getting help to eat or use the toilet. Some residents were found to have been woken up by night-shift care workers, washed and then put back to bed, apparently to make life easier for staff.

A failure to carry out proper checks on staff and poor staff training had also been highlighted by inspectors.

The regulator warned that social care was in a “precarious” state – and according to Age UK the results leave elderly people and their families “playing Russian roulette” when they choose a nursing home or other care service.

Andrea Sutcliffe, chief inspector of adult social care at the CQC, said some of the issues raised by inspectors "have a profound impact on people's lives".

She added: "From a safety perspective, it may be: 'Are there enough staff available to provide the care people need in their own homes?'

"If there is not, it may mean people have missed calls, people may be late to be supported to go to the toilet, to have the food and medication they need.

"These are things you do not want to be happening to your loved one or mum.

"If you're in a residential or nursing home, it may be that there are not enough checks and balances in place to ensure people are getting the right medication and the right support to eat and to drink."

Almost 20,000 people are cared for in the 343 services rated as inadequate.

More than 21,000 adult social care services in England have been given a rating by the CQC in five areas: safety, leadership, and whether a service is caring, effective and responsive to people's needs.

Across these five indicators, 19 per cent of services require improvement, two per cent are inadequate, 77 per cent are good and two per cent are outstanding.

Richard Copson, a disability rights specialist at Slater and Gordon Lawyers, said: “This is yet another worrying sign of the worsening social care crisis, which has been clear for all to see for years now.

“Austerity, budget cuts and a limited interpretation of the Care Act by local authorities have led to unprecedented problems across all areas of the social care sector-care at home, supported living and residential and nursing care.

“But it is perhaps particularly worrying to see such difficulties in nursing care given the increased demand for such care by an increased population of older, vulnerable people.

“As nursing and residential care providers shut down or struggle to recruit carers it’s sadly inevitable that standards slip.

“As a civilised society we should be doing all we can to ensure every aspect of this crisis is addressed – and urgently.

“The Government’s consultation on the future of social care cannot come soon enough when we see daily the troubles vulnerable people face in securing the care they need and the deeply saddening failures of the care system.”