Bogus charity collectors are fleecing hundreds of pounds from shoppers and tourists in Oxford by pretending to be disabled.

Police are warning people not to fall for the scam which is believed to be netting the fake collectors up to £30 an hour.

They pretend to be deaf and unable to speak and then wave a clipboard under people's noses.

On the clipboard is a plea for cash for a fake 'deaf and dumb' charity.

Launching the awareness campaign this week, Pc Vikki Barrie, of the Oxford city centre unit, said about 20 con artists were believed to be operating in Oxford.

They usually consist of a mother and child in their teens with poor English and have been targeting shoppers, tourists and students since April. Pc Barrie said: "We don't tolerate begging in the city. If people are stopped they should ask to see a valid identification - if they haven't got one, they should not be collecting.

"This has been a problem in recent months and while we are making arrests and charging people, we have to make sure they are not tolerated by the public."

In some cases when app- roached by police the fake collectors have been found with £30 in their pocket after just an hour in the city centre.

They are mainly operating in Broad Street, George Street, Queens Street, New Inn Hall Street and St Giles.

The con artists are now taking the clipboard scam to cafes and coffee shops then stealing customers mobile phones when their victims are not looking.

Police spokesman Toby Shergold said the group was foreign, but would not comment which country they are believed to have come from.

Suzanne Lockhart, tourism officer for Oxford City Council, said: "Oxford is seen as a safe destination and we want to keep it that way."

Over coming weeks leaflets warning people to beware of bogus charity collectors will be handed out in the city centre.

Anyone with information or who witnesses the fake charity collectors at work should call police on 08458 505505, or the anonymous Crimestoppers hotline on 0800 555 111.