Lib Dems upset Tories by linking Norris and Jarvis in mayoral election race

The Liberal Democrats have been accused of using "dishonest, cynical" tactics after printing a leaflet that linked Steve Norris, the Conservative candidate for London mayor, to the Potters Bar rail crash.

The Liberal Democrats' election leaflet shows a body being carried from the wreckage near another picture of a smiling Mr Norris, who is chairman of the rail company Jarvis, which admitted joint liability for compensation for victims of the crash. Mr Norris said: "For the Lib Dems to resort to such dishonest, cynical tactics shows how desperate they are. I intend to run a positive campaign on the issues that matter to Londoners, not smears."

The leaflet, which promotes the Liberal Democrats' mayoral candidate, Simon Hughes, carries the headline "Voters Reject Jarvis Boss".

The Liberal Democrats defended the publication of the leaflet. "You can't be chairman of Jarvis and a serious candidate for mayor of London," said Lord Rennard, director of strategy and campaigns. "It's an indication that Steve Norris isn't serious about being mayor of London."

The Health and Safety Executive found that poor maintenance had led to the points failure that caused the crash in 2002 in which seven people were killed and 76 injured. Jarvis maintained the points and said it would pay £3m towards "legally justified" compensation claims.

Polls show Mr Norris is currently second in the race to become London's mayor behind Labour's Ken Livingstone. Mr Hughes is in third place.

Today the Liberal Democrats will launch their campaign for the European elections with Charles Kennedy, the party leader, stressing the environment would be "at the heart of our approach". The local elections campaign will begin next week, and the party will put the emphasis on its plans for a fairer way of raising revenue than the council tax.