The thief takes the card after the victim leaves

It is thought the scam first originated in France and then spread to the south coast of England.

West Midlands Police said it had now arrived in the Midlands.

There were four instances of the con trick at banks in Wolverhampton in one weekend.

There were also a number of incidents in Birmingham.

False friend

A police spokesman said when the victim's card becomes stuck, the criminals claim the same thing happened to them.

"They tell them they know how to retrieve the card," he said.

The "good Samaritan" will then encourage the victim to re-enter their PIN and memorise the number as it is keyed in.

They wait until the user gives up before taking the card out of the machine.

Police are advising people to be careful if their card becomes stuck and someone offers to help.

In this situation the user should not use their PIN while someone is watching, they say.