Police have warned drivers to be on their guard after three cars were stolen in 24 hours by house burglars who simply walked away with the keys.

The first thefts occurred in Halifax Road, Leavesden, between 10pm on Tuesday, October 20 and 6.15am on Wednesday, October 21.

Thieves forced their way through the front door and took two sets of car keys and a wallet from a bowl the living room.

After collecting a lap-top computer they drove away with a black Mercedes and a BMW.

The third happened between 10.30pm and 5am in Gallows Hill, Abbots Langley, where a grey Mazda hatchback was closed.

Detective Inspector Jeeta Aulak said: “We would advise residents to ensure their keys are kept out of sight.”

Anyone with information is asked to telephone 0845 33 00 222.