Thieves are stealing doorstep collection bags or posing as charity officials to swindle cash out of kind-hearted Bradford residents.

A pensioner was door-stepped by bogus charity officials late at night in Great Horton, a charity van driver was threatened by youths in Wibsey and two doorstep collection bags were stolen in the same day in Pudsey.

Today, Harold Wilkinson, aged 70, of Old Road, Great Horton, told of his experiences and warned others not to be fooled.

He said: “They came round about three months ago with T-shirts on with Oxfam written on them and they had identity cards round their necks. I sent them away and called the police.

“Then they came knocking again at 9pm on Wednesday. There were two or three of them. I shouted through the letter box.

“They said they were collecting money for Oxfam. I phoned Oxfam the morning after and they said they never sent anyone door-to-door collecting, so these people were tricksters preying on the good name of a charity.”

On two occasions in the last week, British Heart Foundation volunteers arrived at houses in Pudsey to find that thieves had made off with collection bags.

Christine Tyson, manager of the BHF shop in Northgate, Bradford, said: “I can only guess that they are weighing the contents in to get the money back from the rags.”

Rosie Hotte, assistant manager at the Marie Curie charity shop in Ivegate, Bradford, said: “It’s a bit alarming really. We have had quite a few vans turning up to find that bags have gone. I personally think they are taking it to the rag place.

“Our van driver has been threatened as well by three youths on scooters in Wibsey.”

A West Yorkshire Police spokesman said: “If people see anything suspicious, they should report it to us immediately.”

e-mail: will.kilner@telegraphandargus.co.uk