Police outside the Waitrose store in Ashford – one of three shops targeted by ram raiders last month

Police investigating a string of attempted and successful cash machine thefts in Kent have made another eight arrests.

The men, aged between 18 and 30 years old, were arrested at addresses in Gravesend, Longfield, Maidstone, Orpington and Sevenoaks yesterday.

It comes after a £25,000 reward was offered for information leading to the charge and conviction of the thieves responsible for three thefts last month.

On November 16, thieves used a digger stolen from a building site to rip a cash machine from the ground outside a Waitrose store in Ashford. The stolen ATM was later found empty on a country lane between Hothfield and Pluckley.

Three days later, another digger was used to demolish part of the NatWest bank in High Street, Snodland. The offenders fled the scene empty-handed when police arrived.

Ram raiders also struck at the NatWest bank in Snodland (above) and a Co-op store near Sittingbourne (right)

On November 22, an ATM was stolen from the Co-operative store in High Street, Newington, near Sittingbourne. The cash machine was found abadoned but intact in a field close to the A2.

Det Ch Insp Keith Davies of the Kent and Essex Serious Crime Directorate said: "The theft of cash machines is a national problem – it isn't unique to Kent and police have been working for some time with the ATM industry to improve security measures which make the machines more difficult to steal and easier to track if taken. This includes the use of Smartwater which will uniquely stain the money inside the machine.

"Police have also talked to building firms about ways in which they can ensure plant machinery is secured to reduce the opportunity for thieves to use them in an attempt to steal cash machines.

"The public can also help police by calling 999 if they see any unusual movement of diggers and similar plant machinery at night or people acting suspiciously near banks or shops with cash machines."

The eight men arrested yesterday have all been bailed while police continue their investigations.

In total, 11 people have now been arrested in connection with last month's thefts.