FIREFIGHTERS have issued a warning to be wary of faulty Christmas lights over the festive season.

A dramatic video showing the effects faulty lights can have on a dry tree has been released by the London Fire Brigade.

The video shows how a broken light can spark an inferno on a Christmas tree that could spread to the whole room in less than a minute.

In seconds, the video shows a living room enveloped with fire.

The London Fire Brigade warned: "Check your Christmas tree lights are in good condition and turn them off before you go to bed.

"Marke sure you have working smoke alarms."

In an emergency always call 999.