Student union leaders today urged people not to buy unofficial rag mags on sale in the city.

The University of Bradford Student Union fears that conmen posing as students have been selling the magazines to unsuspecting members of the public.

Official rag mags contain jokes and information about the charities to which the proceeds go and are usually sold during a university's rag week.

But sellers are touting magazines around the city centre for 99p - saying the money is for Bradford students.

When two sellers were approached by the Telegraph & Argus and asked whether they were from Bradford College or the university, they claimed to be from Blackpool and Fylde College.

However the college today denied any knowledge of them.

One seller said: "We are mature students and it's like the Big Issue. We pay 60p for the mags and then it's up to you whether you keep the profits to pay for things like exams. We just felt like a day out to Bradford.''

They claimed they did not tell anyone the money was going to charity.

The magazine contains a few pages of crude jokes and has no indication on it anywhere about who produced or printed it, apart from saying there are contributions from various universities.

But Neil Drayton, University of Bradford student union communications officer, said: "Our rag week is not until May 21 and our rag mag is worth 'at least 50p'. We ask for a donation rather than sell it. We have heard of people selling rag mags under the name of Bradford University before and the student union does not endorse them.

"I would urge people not to buy this unofficial mag but feel free to buy our own which are clearly billed as University of Bradford Union. They also have our ram logo on the front.''

When the T&A contacted Blackpool and Fylde College a spokesman said they had no knowledge of students from their college selling mags.

Press officer Lynette Horsburgh said: "These are nothing to do with us and we are thinking of taking legal action.''

Graham Hebblethwaite, divisional manager for West Yorkshire Trading Standards, said: "It seems like one of 1,001 ways of making a fast buck.''