The Western Health Trust has confirmed that all planned operations due to take place today at Altnagelvin Hospital have been cancelled due to an overnight fire.
120 patients were moved from their wards in a major evacuation operation at the hospital following the fire which broke out on the top floor.
It is now thought this lead to a plastic water pipe bursting forcing the evacuation of seven floors -there were no injuries.
It is the second fire in the old block of the hospital in recent weeks leading to calls for an investigation to be carried out to ensure it is safe for returning patients.
Health Minister Edwin Poots will today (Saturday) visit the hospital to meet with staff and patients.