Devon, Cornwall and Somerset hospitals put on 'black alert'
"Black alerts" in hospitals have been extended across south-west England, NHS bosses have confirmed.
The news comes as Plymouth Hospitals Trust in Devon confirmed it has been on the alert - the highest level the NHS has - since early January.
Yeovil Hospital in Somerset is also now on the alert, while hospitals in Exeter and Dorset are under pressure.
The alert indicates a hospital has officially confirmed its services are overwhelmed by demand.
Extension of it comes after the Royal Cornwall Hospital Trust confirmed it was on the alert status, last Tuesday.
Analysis: Sally Mountjoy, Correspondent, BBC South West
The last time hospitals were this busy was six years ago, NHS England says.
Almost all hospitals in the region have seen sharp increases in patients and they're finding it increasingly difficult to cope.
Derriford now admits that, since the start of the year, it has been in "critical internal incident mode", jargon for the highest level of escalation - or a state of "black."
The majority of emergency admissions are older people with respiratory problems. One exacerbating factor may be that this season's flu vaccine is largely ineffective against the strain of the virus currently in circulation.
Austerity has also taken its toll. Despite a cash injection to help manage "winter pressures", years of flat incomes have dented hospitals' resilience, while spending cuts by hard-pressed councils mean less money for the care packages needed to allow frailer patients to be sent home after treatment.
A spokesman for Plymouth Hospitals Trust said: "Since the end of December, we have faced unprecedented and sustained demand on our emergency and medical services, which has impacted right across the hospital."
The spokesman said the hospital had been in "critical internal incident mode" since early January, which is nationally recognised as a "black alert".
Torbay and the Royal Devon and Exeter Hospital has been on red alert for the past week and Dorset County Hospital has announced a red alert - one level below black.
Kevin Baber, chief operating officer at Plymouth Hospitals Trust, said "a number of operations" had been cancelled.
In a statement on the trust's website, he said: "As more patients are admitted from the emergency department onto wards, beds get taken up.
"This means we don't have beds available for those patients coming in for planned operations, with a particular lack of critical care beds, and therefore we have to cancel their surgery."
Ben Bradshaw, Labour MP for Exeter and former health minister, said he was told the volume of patients being admitted to the Royal Devon and Exeter Hospital had led to the cancellation of all operations on one day.
He said: "This is very worrying and it shows the unprecedented pressure that our hospitals and our A&E departments in particular, are under."
At the Royal Cornwall Hospitals Trust, which covers St Michael's in Hayle, West Cornwall Hospital in Penzance and The Royal Cornwall at Treliske, 280 beds have been blocked so far by people who were fit to leave but had no care package in place.