The number of people phoning 999 appears to have dropped in parts of England as thousands of ambulance staff and paramedics strike until midnight.
The West Midlands Ambulance Trust thanked people for heeding their advice to only call in an emergency as ambulance trusts reported receiving fewer calls.
The drop in calls comes as health leaders have urged people to still phone for an ambulance if they are in a life-threatening emergency.
It is feared some people in desperate need of help will not phone 999 during the strike action.
Hundreds of members of the army, navy and RAF have been drafted in to cover as paramedics, technicians, control room workers and other staff in England are on strike.
All Category 1 calls (the most life-threatening, such as cardiac arrest) are being responded to during the walkouts, while some ambulance trusts have agreed exemptions with unions for specific incidents within Category 2 (serious conditions, such as stroke or chest pain).
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‘We want to reassure patients’
Dr Adrian Boyle, president of the Royal College of Emergency Medicine (RCEM), said: “There may be a number of reasons why 999 calls are dropping – hesitancy may be a key factor during the industrial action.
“We want to reassure patients and the public that if they need emergency care, A&Es remain open.”
The Welsh Ambulance Service has said demand is “manageable” but any “influx of calls would put significant pressure on our service”.
Meanwhile, the East Midlands Ambulance Service said it was too early to say how the service was coping.
Up to half of its more than 4,000 workforce were GMB members who were striking.
South Central Ambulance Service said its main impact from strikes was patient transport services in Sussex and Surrey, rather than urgent and emergency care services.
The London Ambulance Service declined to comment on how services were running.
Thursday and Friday ‘expected to be busy’
Meanwhile, a chief executive of a large northern teaching trust told the Health Service Journal (HSJ) it had “so far not (been) as bad as I’d feared in terms of hospital pressures – in fact, (emergency departments) are less pressured than usual.
“We haven’t seen cars/taxis with patients arriving in large numbers but the problem is that much of the risk is not currently visible to us given people will be at home.
“We therefore expect very busy days on Thursday and Friday.”
It comes as the Royal Albert Edward Infirmary in Wigan declared a critical incident and said it was full after facing “unprecedented pressures” in its A&E department.
The strike action has taken place as there is a bitter war of words between unions and Health Secretary Steve Barclay who has said he will not back down on pay.
Health secretary accused of ‘blatant lie’
Mr Barclay said the Unite, Unison and GMB unions had “refused” to work with the government at the national level to set out plans for dealing with the strikes.
But the unions said all those agreements had been made locally and were in place.
From a picket line in Longford, Coventry, Unite general secretary Sharon Graham accused Mr Barclay of a “blatant lie” for saying ambulance unions had taken a “conscious decision” to inflict harm on patients.
Meanwhile, a paramedic in Nottinghamshire said patients’ lives have been at risk for a long time due to issues in the NHS.
Tom, 33, from the East Midlands Ambulance Service, said: “I’ve attended elderly patients who have been on the floor with broken hips for over 20 hours.
“They’ve been waiting that long that their limbs have started to become necrotic (dying tissue), resulting in major surgery to remove said limbs.”
‘Don’t get blind drunk’
A former Royal Marine who is among striking health workers described it as “demoralising” to spend entire shifts waiting outside hospitals with patients stuck in the back of ambulances as he demanded “something needs to change”.
Harry Maskers from Cardiff, who works for the Welsh Ambulance Service, said that while he was unable to strike during his military career, he was taking the opportunity to do so now, with “the kicker” being the government’s refusal to discuss the issue of pay.
Mr Barclay had earlier urged the public to “use their common sense in terms of what activities they do” while ambulance workers are on strike, while the medical director of NHS England Professor Sir Stephen Powis urged people not to get “blind drunk”.
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The walkout by ambulance staff and paramedics comes as nurses in Scotland overwhelmingly rejected the latest pay offer from the Scottish government, in a move which could see members of the Royal College of Nursing (RCN) take strike action for the first time ever.
Meanwhile, National Highways workers will go on strike from Thursday until Christmas Day in the latest phase of industrial action by the biggest civil service union.
The strike involves members of the Public and Commercial Services union (PCS) working as on-road traffic officers and regional operating centre operatives, in London and southeast England.
It comes as planned strikes by railway cleaners in a dispute over pay have been called off.
More than 1,000 cleaners, who are members of the Rail, Maritime and Transport union, would have been involved.