A tractor and a bulldozer were among the items of gardening equipment stolen from two building sites in Three Rivers this week.

Police fear the two crimes were committed by "professional" criminals who may be intent on striking again.

Earlier this week, thieves stole equipment worth almost £50,000 from a building site in London Road, in Rickmansworth.

The theft occurred between 4.30pm on Sunday afternoon and 6.30am on Monday.

Then, a plant tipper was stolen from Farm Way in Northwood. Police believe the theft took police between 4.45pm on Tuesday and 7.45am the following morning.

Officers are also keen to hear from any residents who live in the London Road area of Rickmansworth or in the Farm Way area of Northwood, especially if they have seen or heard anything suspicious during the past few nights. Anyone with any information can telephone 0845 33 00 222.