GAS cylinders were used to blow up a cash machine in an attempted bank robbery in Coulsdon in the early hours of Sunday morning.
The police were called to NatWest, in Brighton Road, just before 4am where they found significant damage to a cash machine.
An hour earlier a branch of NatWest in Warlingham was targeted by balaclava-clad men using the same method.
Speaking about the Coulsdon raid, a Metropolitan Police spokeswoman said: "It is believed the bank was broken into using gas cylinders because debris was found at the scene which suggested an explosion had taken place as part of the robbery."
A suspect fled the scene and detectives from Flying Squad are investigating. No arrests have been made.
Surrey Police linked the robbery to a similar incident in Warlingham just before 3am the same morning, where men in balaclavas used an explosive to try and break into a cash machine at the NatWest bank on The Green.