The ongoing problem of fraudsters targeting senior citizens with sophisticated phone scams has taken a new turn, as the criminals have begun using a technique that involves them showing up at victims’ homes to collect their debit cards.

The scam is an extension of a common phone fraud technique in which criminals call victims–typically senior citizens–and inform them that they have identified some fraud on the victim’s account. The callers often pretend to be from the victim’s bank, saying that they have discovered some problematic transactions on the account and need to confirm some personal details in order to fix the issue. They sometimes will ask for the victim’s account number, PIN, and other details, and then use those details in order to steal money from the account.

In some newer cases, the caller will tell the victim that the bank is issuing her new credit or debit cards and that he just needs the PIN on the card in order to cancel the existing cards. The criminal promises that the cards will arrive in the mail the next day, and will then call back to ask if the cards came. When the victim says no, the fraudster will then send a courier to the victim’s house to collect the old cards, as a courtesy, and then the criminals will immediately use the cards to withdraw money from the accounts.

“Telephone fraud has traditionally been a faceless crime, but criminals are now defrauding victims over the phone before collecting their cash cards in person. This poses all kinds of risks to the individual concerned, let alone the financial losses they will incur if they are conned,” said Detective Sergeant Garry Knight, of Bournemouth Criminal Investigation Department in the U.K., in an alert on the scams Tuesday.

The physical component of this scam is unusual, as most phone fraud schemes are designed to succeed solely on the basis of the phone calls. And in other twist on these calls, the caller will pose as a police officer and tell the victim that he is from the fraud department and ask the victim if she has authorized a given transaction. In a call recorded by the Dorset (U.K.) Police, the criminal uses this ruse on his victim, an elderly woman, and then instructs her to call the emergency services number (999) immediately to verify the problem. The scammers in this case will leave the phone line open, rather than hanging up, and when the victim dials 999, she is again connected to a scammer.

“We have reason to believe that you have been frauded, that someone has made a fraudulent transaction in your account in the amount of 1000 pounds. Can I just confirm that that was you?” the scammer says in the recorded call.

The fraudster claims to be from the “Visa fraud department” at the police department, and tells the victim that she should call 999 as soon as possible in order to ix the problem.

“The sooner you do that, the better,” he says.

This kind of phone fraud has emerged as a serious issue in a number of countries, and the U.K. has seen more than its share of it. Police in Dorset estimate that various phone fraud scams have cost residents almost £1,100,000 since 2014.

“Nobody, no matter which organisation they claim to be from, will ask you for bank details over the phone or on your doorstep. This includes the police, banks and retailers.,” Knight said.