A couple were left shaken up after a rag soaked in flammable liquid was lit and shoved through their letterbox today.

Fire crews were called to the blaze in a first-floor flat in Thorold House, Fairhaven Green, Idle, Bradford, at 2am.

Smoke alarms in the flats alerted firefighters from Idle and Rawdon to the blaze which was out on arrival.

No one was hurt in the fire though there was some damage to the flat.

A spokesman for West Yorkshire Police said they were treating the incident as arson and would be liaising with the fire service.

A spokesman for Idle fire station said the incident showed the importance of smoke detectors.

He stressed they give a valuable early warning which can make the difference between escaping safely from a property and having an exit route cut off.