Patients have been evacuated due to a suspected gas leak at the James Paget University Hospital in Gorleston, near Great Yarmouth.
Three crews from Norfolk Fire and Rescue, one from Great Yarmouth and two from Gorleston are on scene along with police and the ambulance service.
The fire service have been on scene since 10.40am.
Graham Wilde, chief operating officer at the James Paget University Hospital, said: 'We are dealing with a suspected gas leak.
'As a precautionary measure patients have been horizontally evacuated to a place of safety whilst the estates team and the Fire Brigade investigate.
'The fire alarm sounded to restrict access around the site. All areas are now open with the exception of the affected ward and corridors.'
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