Pressure is mounting on highways chiefs to refund fines given to motorists who used 24-hour Olympic bus lanes after it emerged they may be invalid because of a technicality.

Civil liberties group Big Brother Watch is calling on Barking and Dagenham Council to cancel the 11,000 tickets which netted more than half a million pounds during the Games.

The civil liberties group spoke out after a Barking motorist had his �130 fine quashed on appeal because the traffic management order under which the fines were issued was imposed under a chapter of traffic regulations that does not exist.

The fines appeal body, the Parking and Traffic Appeals Service, also ruled the motorist had been misled into straying into the bus lane in Longbridge Road in July because normal bus lane signs had not been covered or taken down for the Games.

Big Brother Watch director Nick Pickles said: “The council should recognise its actions were not legal and return any illegally enforced penalties.

“You can’t get to a situation where councils can pick and choose the rules they follow. They made a mistake and they should say sorry and return the fines they gained from an unauthorised camera.”

The Parking and Traffic Appeals Service quashed the fine issued in Longbridge Road, Barking, on December 3.

The service ruled the Barking and Dagenham Council traffic management order was “unenforceable” because it was imposed under chapter 8 of the Traffic Signs Regulations and General Directions 2002, and chapter 8 does not exist.

A spokesman for the service said the appeal decision applied to this particular fine and stressed it did not set a precedent.

But one reader Eddie Williams said: “The council should cancel all penalty charge notices issued during the Olympic period and refund in full those who have paid.”

Another driver Mark Rider told the Post: “All I want to see is every motorist who were fined for being in these Barking and Dagenham bus lanes refunded.”

A Barking and Dagenham Council spokesman said: “We are aware of this decision from PATAS. We are reviewing our position with regard to bus lane fines issued during the Olympic period.”