Nearly 50 patients were removed from the hospital's cardiac wing
A blaze at London's Great Ormond Street children's hospital has forced the evacuation of nearly 50 patients and hundreds of family members and staff.
The fire started at about 0830 BST on the cardiac wing and caused an oxygen gas cylinder to explode.
The entire wing was cleared, including a number of children who were being anaesthetised for surgery, but there were no reports of patient injuries.
The blaze was brought under control by a team of 30 firefighters.
Two ambulances and a hazardous area response team, specialists in dealing with other risk factors like chemicals and gas canisters, were also sent to the site in Russell Square, central London.
The London Fire Brigade said four firefighters suffered minor effects of smoke inhalation and were treated at the scene.
The hospital's chief executive said the emergency plans had worked well
The hospital's chief executive Dr Jane Collins said its major incident plan was put into place very quickly during the blaze, as patients were led to safety from the cardiac wing.
"There were some children who were due to have surgery this morning so they were already in the process of being anaesthetised," Dr Collins said.
"We have already woken these patients up because we want to make sure they are in a stable and safe situation."
Patient Laura Bryan had been at the hospital with her baby son Finlay on Monday, as she was due to find out whether she could be his kidney donor.
Outside the hospital she said: "We were waiting in X-ray and we could smell burning and everything.
"The alarm was going off, we were just about to evacuate and there was an explosion, so we ran out here."
Cleaner Temitope Olowu, who was working in the hospital, said: "We were suddenly told there was a fire on our floor, level five, so we were all ordered to the nearest fire exit.
"We didn't really know what was happening. Everyone was keeping calm and just concentrating on getting out of the building."
All outpatient and day cases were cancelled on Monday, and cardiac patients were moved to other parts of the hospital. The hospital continued to accept emergency patients, however.
A hospital spokesman said it expected to accept all planned cases from Tuesday.
Day patients who arrived for treatment were sent home