ANAESTHETISED youngsters who were about to have operations were among patients and staff evacuated from the world-famous Great Ormond Street children's hospital after a fire and explosion today.

ANAESTHETISED youngsters who were about to have operations were among patients and staff evacuated from the world-famous Great Ormond Street children's hospital after a fire and explosion today.

The blaze, which is thought to have involved a gas cylinder, happened in the cardiac wing of the London children's hospital at around 8.30am this morning..

No patients or staff were hurt, but four firefighters suffered minor injuries while tackling the fire and were treated by paramedics at the scene.

Dr Jane Collins, the hospital's chief executive, said the explosion was probably a medical gas cylinder and the cardiac wing may have to remain closed for some time.

There were up to 40 patients in the wing at the time of the blaze, and some will now have to be transferred to nearby hospitals.

It is not yet clear what caused the explosion or the fire. An investigation will now be carried out.

Six fire engines and about 30 firefighters were sent to the hospital.