The tiny bells are attached to purses or wallets and the idea is that the victim and other people will hear them before the thief runs off.

Bulwell town-centre beat manager Pc Joe Homan said there had been a worrying spate of "despicable" thefts from elderly people.

"The offenders have been working in pairs, with one distracting the victims while the other grabs their valuables," she said.

"These people should be ashamed of themselves. They are obviously aware that the elderly cannot run after them.

"Card shops are one of the places they choose. One will gain a victim's attention by showing them a card and asking if they think it is suitable for a child of a certain age.

"Meanwhile the accomplice will creep up from behind and snatch what they can from the victim's bag."

Pc Homan said there had been ten such thefts in the town centre last month alone.

"Most of the victims were women but there was one man who had his wallet stolen," she added.

Pc Homan has handed out about 200 bells, coloured red, blue, green and gold, but has no more available at present.

However she pointed out that they were available in pet shops for 50p.

Pc Homan warned people to keep purses, wallets and other important items out of view while shopping.

"People sometimes tend to leave their purse on top of their bags," she said. "Some younger women may leave it on top of their pushchair as well, which makes them just as vulnerable."

Sylvia Matthews (76), of Ragdale Road, Bulwell, who has been given an alarm bell for her purse, said she thought they were a very good idea.