THE barking of the family dog saved a family who had to flee their home after an arson attack in the early hours of Friday, August 23.

The mother, father and their two young sons were woken by the dog barking just after 3.30am and found the front porch blazing and the two-storey house in Headstone Lane, Hatch End, filling with smoke.

The parents, whose names have not been released by police, got the children to safety in the back garden before alerting a neighbour who called the emergency services.

Firefighters from Harrow tackled the blaze, but a London Fire Brigade spokesman said that 10 per cent of the ground floor was badly damaged. The family were treated at the scene for shock and the affects of smoke inhalation.

The brigade's fire investigations unit was called in when it was discovered that an inflammable liquid, possibly petrol, had been poured through the letterbox. DC Steve Everett, who is leading Harrow police's investigation into the attack, said that the family had been lucky to escape alive.

"We could easily have been dealing with a much more serious crime," he said. "It was in the very early hours of the morning and all of the family were in bed asleep. It is very fortunate that they woke up and were able to escape before the fire spread.

"As a result of information passed to us by the brigade's investigations unit the fire is being treated as suspicious and a scene-of-crime officer spent the following morning searching for evidence. I am very keen to speak to anyone who was in the area at the time and may have seen anything suspicious, either before or after the fire."