A 13-year-old boy, who jumped from a third-floor flat in St John 's Wood to escape a fire, has died in hospital.

A 13-year-old boy, who jumped from a third-floor flat in St John 's Wood to escape a fire, has died in hospital.

The blaze swept through the flat just before 3am this morning in Cunningham Place.

He was being treated after jumping from the window and died as a result of his injuries.

The body of his sister, believed to be aged five or six, was also found in the flat when fire crews arrived at the scene.

Two other brothers, aged 12 and 15, were taken to hospital along with their

father, aged 44. All three remain in hospital in a serious but are not believed to be in life-threatening conditions.

More than 20 firefighters from north Kensington, Paddington and Belsize tackled the blaze for more than an hour.

Press liaison officer Andy Pike said: “We all like to save lives, we never like to lose them and we like to lose youngsters even less. They (firefighters) will be thinking about their nieces and nephews.”

The cause of the fire is under investigation. A Metropolitan Police spokesman said a 32-year-old man was arrested near the scene.