The BBC has uncovered four fresh instances of viewer deception as an internal investigation revealed an ‘underlying problem’ with the Corporation’s editorial controls.

The new examples of fakery include changing the result of a poll to name the Blue Peter cat.

A BBC spokesman refused to confirm reports that former Blue Peter editor, Richard Marson, has been sacked.

The other breaches concern the Tom Robinson Show and the Clare McDonnell Show on BBC 6 Music, and Film Cafe on the BBC Asian Network.

They join Children In Need, Sport Relief, Comic Relief, the Liz Kershaw Show on 6 Music, children’s show TMI and the BBC World Service’s White Label programme on a list of shows which have deliberately duped viewers.

In a new report, the BBC Trust said: “While these breaches represent a very small number of the programmes broadcast in the last two years, they indicate an underlying problem in non-news areas that management has failed to apply satisfactory editorial controls.”

The Trust issued its statement after receiving a report from director-general Mark Thompson.

It reserved its strongest criticism for the instances involving Comic Relief, Sport Relief and Children In Need.

“The connection of some serious editorial breaches with programmes designed to generate charitable giving is concerning and risks damaging the very charitable causes the BBC supports,” the statement said.

It added the Trust is clear these cases arose “because of some programme-makers’ misguided belief that these decisions were in the interest of the programme and that that was more important than honesty and fairness to the audience”.

The Trust’s requested a code of conduct be put in place.

It said some cases came about because no winner was forthcoming.