Police in Leeds and Wakefield are warning people to be on their guard against doorstep conmen tricking their way into pensioners' homes pretending there are burst water mains or frozen pipes.
On Wednesday two men called at the home of a 93-year-old man in Victoria Street, Pudsey, telling him they were from the water board and there had been a burst water main.
One had a clipboard and asked the pensioner to write down his details while his accomplice searched the property.
The man became suspicious and asked them to leave.
The man with the clipboard was white, clean shaven, had a fair complexion and short dark brown hair.
He had a local accent and wore a dark blue jacket. His accomplice was white, 5ft 10ins tall, and wore a similar jacket.
On Tuesday two men called on a couple, aged 78 and 79, in Henconner Lane, Bramley, telling them there was a frozen pipe.
Once inside they asked the couple to write down their details on a clipboard while one man went upstairs. The woman said she was calling the police and both men left in a large silver or grey car.
One man was white, aged in his mid forties, and about 5ft 8ins tall. He wore dark clothing.
The second was also white, in his late 20s, 6ft tall and slim. He wore a dark, three-quarter length coat and yellow workman's hard hat.
Cash was stolen from the home of an 80-year-old woman in Harrison Avenue, Bramley, after two men bluffed their way in saying they needed access to water pipes on Monday .
Det Insp John Dexter said: "Criminals who target the elderly and vulnerable are utterly beyond contempt. From the recent incidents it's clear they are using the cold weather to bluff their way into people's homes. The use of a clipboard and hard hat are part of the act."
Anyone who saw the men or who has information can ring PC Lee Swift on 0845 6060606, or Crimestoppers on 0800 555 111.