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Emergency services at Lincoln hospital A&E
A man has been arrested on suspicion of arson after a fire closed the accident and emergency department at Lincoln County Hospital.
Patients and staff were evacuated from A&E at about 03:00 BST, said United Lincolnshire Hospitals Trust (ULHT).
Lincolnshire Police said no-one was injured, but the blaze caused "extensive damage" to the department including, X-ray, CT and MRI scanners.
The 57-year-old arrested man remains in police custody for questioning.
The fire started in a radiology room, with affected patients being cared for in other areas of the hospital, ULHT said.
Lincolnshire Fire and Rescue Service extinguished the blaze, with ambulances diverted to neighbouring hospitals while Lincoln A&E is closed.
"We believe this to be an isolated incident and we will remain on scene and in the local area over the next few days while we make our enquiries," police said.
Officers have asked anyone with phone or dashcam footage from in or around the A&E department between 02:40-03:15 to get in touch.
One A&E patient, Milly, said: "I'm fine. Surprisingly, it wasn't scary. We didn't even think it was a fire until we came outside and saw the smoke and orange glow over the building, it looked like a sunset really.
"There were a lot of patients outside but it was calm, there wasn't any panic or mayhem, the staff were really calm and offered us blankets because it was freezing.
"The critical care patients were put in ambulances and after about 20-30 minutes we were all taken inside to outpatients."
The trust declared a major incident and said anyone needing non-life-threatening urgent or emergency care should call 111 or visit NHS 111 online for advice.
People should continue to call 999 for life-threatening emergencies, it added.
ULHT added: "While we work to reopen our Emergency Department, we ask that you do not to attend."
Patients who were due to have an X-ray, CT or MRI scan on Tuesday are also asked not to attend the hospital.
Speaking to BBC Radio Lincolnshire, Andrew Morgan, ULHT chief executive, said outpatients were being contacted about appointments and would be told whether or not they were going ahead.
He added: "We do apologise to those who we couldn't get to quickly enough and had to be turned away.
"We are trying to get things back up and running but there is substantial fire damage, and also smoke and soot, and that is why we have had to change some services."
He said he could not give a time or date when A&E would be able to reopen.
"Until we are assured of both the cleanliness and the safety of both the urgent treatment centre and the A&E there is no way we can let people back into it," he said.
The fire service said six crews were called to extinguish the fire using a hose reel jet, breathing apparatus, a portable pump to ventilate and a thermal imaging camera.
Northern Lincolnshire and Goole NHS Foundation Trust, which runs A&E departments at Grimsby and Scunthorpe hospitals, said both were taking patients from Lincoln and continued to be "very busy".
A spokesman said: "Anyone coming to A&E who doesn't need urgent emergency treatment is likely to have a long wait, as we will always prioritise seeing patients in the greatest need of our care."
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