Fraudsters stole £300 from an 89-year-old woman in Gravesend after convincing her to hand over her bank details.

May Gorvan, from Gravesend, is one victim of a new "courier scam", used to obtain pin numbers of elderly and vulnerable Kent residents.

She received a call from a man claiming to be from the police. He urged her to ring her bank after telling her of fraudulent activity on her bank card.

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But when she put the phone down to contact the bank, the man kept the line open so he could listen in on details given out.

May was told to put the cards in an envelope and seal them, and someone from the bank would collect them from her front door.

After handing the cards over, she noticed £300 missing from her account prompting her to call the police.

Video: May Gorvan describes how she fell victim to the courier scam

May said: "I have always been conscious of keeping my cards close to me, it makes me feel as though I was an idiot to let him get away with it.

"If it happens to anybody and they are suspicious, put the phone down and the ring the police. I wish I had done it in the first place."

Police have released a video of May's experience in an attempt to warn other residents of the dangers.

DCI Keith Davies, head of serious economic crime unit at Kent Police, said: "The very sad case and endictment of this particular trend is that the criminal fraternity are targeting the vulnerable and elderly in our community because they are trusting of authority."

Police say the "courier scam" is being used via new phone apps allowing fraudsters to use a fake caller ID to show they are calling from a legitimate bank.

When targeting victims, they ask them to check the ID to validate the call before asking for information to take funds from their bank accounts.

Detective Sergeant Adrian Brown said: "Unfortunately these phone apps are both cheap and easily available.

"Our advice is simple; never give your bank details out to anyone who calls you directly.

"If you are concerned about the security of your account then attend your bank in person or use the contact details provided by your bank to contact them directly, preferably from a different phone to the one you received the call on.

"Never ever give out your account information out to someone who canvasses your call.

"In some instances banks will not cover these breaches of security and it is the individual who loses out financially, never being able to re-coup their losses."