Questions have been raised over the number of GPs available out of hours in Norfolk, Waveney, and Wisbech.
It comes after a member of staff at IC24, the company which runs provision in the region, claimed just one GP had been covering the area - which has a population of more than 1.1m - for six hours in the early hours of the morning earlier this month.
IC24 denies this was the case and a spokesman said 'we had seven clinicians providing a service in Norfolk, Waveney and Wisbech. Two of those clinicians were GPs, and five were urgent care practitioners'.
But an internal report seen by this newspaper, but contested by IC24, showed the GP in question had raised concerns that he was the only doctor on shift and needed back up.
An anonymous staff member said: 'This meant he would be expected to cover palliative visits for the whole area, mental health issues and anything else that needed GP input. This is clearly unsafe and should not be allowed to keep happening.'
GPs in the out of hours service speak to patients on the phone to provide help, support the non-clinically trained team and can also go out on home visits if necessary.
Often other healthcare professionals such as urgent care practitioners are also on shift, or call handlers can give patients advice, direct them to another service, or if needed call an ambulance.
Alex Stewart, chief executive at Healthwatch Norfolk, said: 'The first problem would be patient safety and the quality of service provided. The other problem is the NHS is saying don't go to A&E but people will if they can't get the help. It makes it even more confusing for patients.'
A leaked email late last year found a similar situation in Kent, where two GPs were left to give out-of-hours cover for 1.4m patients under IC24.
The email had said that 200 patients were forced to wait for visits or medical advice and the service's delivery manager Lesley Williams branded the situation 'unsafe'.
An IC24 spokesman said: 'Our staffing levels are set according to validated data relating to demand. As patient numbers are considerably lower overnight, so is the number of clinicians on duty. As of midnight we had 39 cases that had been referred to the out of hours service, and this number steadily reduced throughout the night.'
In Norfolk and Waveney IC24 has not hit targets of answering 95pc of calls within 60 seconds since November 2017, but the number of abandoned calls has dropped.
And NHS England statistics showed the service answered 32,346 last month - nearly 7,000 more than in November.
Liberal Democrat MP for North Norfolk and former health minister Norman Lamb said: 'When I think about the constituency I represent, there are very many elderly people, often in very remote areas, [out-of-hours] is for them a lifeline.
'And it's very important we avoid unnecessary visits to hospital.
'If you need help, or you're a loved one, in the middle of the night you need to be sure you can get access to the care you need.
'It can be incredibly worrying and stressful waiting for someone to offer help, either by phone or in person.'
Clive Lewis, Labour MP for Norwich South, added: 'IC24 isn't one of the usual corporate vultures who squeeze our NHS for profits while shortchanging on us on service.
'It is no coincide that out of hours services are in crisis all over country. So I can only assume that what were seeing are yet more symptoms of the Tory NHS recruitment crisis and their chronic underfunding of our health service.'
The IC24 spokesman added: 'Our staffing model consists of a team of multidisciplinary clinicians competent in delivering urgent primary care, led by GPs, and including Advance Nurse Practitioners (ANPs) and Urgent Care Practitioners (UCPs). This is a national approach to delivering face to face urgent primary care, unlike the traditional model of out of hours care, which was entirely dependent on GPs. The urgent care workforce mirrors the changes that have also been made in the modern in-hours primary care workforce of GPs, ANPs and UCPs.
'Last week our call handling performance was at 89.7pc, compared to a national average of 74.09pc, and we report to our commissioners on a weekly basis in respect of performance and workforce.'
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