Thousands of voters were baffled by the ballot papers which saw Labour's Ken Livingstone re-elected as London Mayor and a strong showing by the Tories and UK Independence Party.

Despite a slightly increased turnout of 35.97 per cent, up 2.32 per cent from 2000, 56,862 of the 1,863,671 first-choice votes cast for the mayor could not be counted as they had not been filled in correctly.

A spokeswoman for London Elects, which managed the elections, said: "People still aren't familiar with the system. It could be people not understanding that they have a second choice or people overvoting - marking both choices in the same column. We hope these figures will go down as people become more familiar with what they are doing." A large number of second-choice votes - 329,090 - could not be counted either.

Mr Livingstone received 685,541 first-choice votes - 36 per cent of the total and seven per cent more than his nearest challenger, Conservative candidate Steven Norris, who received 29 per cent of the first-choice votes. Because neither had achieved more than half of the votes, second-choice votes were added to the total. Mr Livingstone received about 18,000 more second-choice votes than Mr Norris, making him the winner.

In Barnet and Camden, Conservative Brian Coleman won 35 per cent of the vote to keep his seat on the London Assembly. Mr Coleman won 47,640 votes, massively increasing his majority over Labour from just 500 votes in 2000 to more than 11,000.

The Tories now have nine seats on the 25-seat London Assembly - two more than Labour. The Lib Dems have five seats, the Green Party has two and the UK Independence Party also won two seats.

Lucy Anderson, the defeated Labour candidate for Barnet and Camden, won a disappointing 27 per cent of the vote. Liberal Democrat Jonathan Simpson got 17.48 per cent, the Green Party's Miranda Dunn received eight per cent. Magnus Nielsen (UK Independence Party) won six per cent, Elisabeth Wheatley (Respect party) got three per cent and Humberto Heliotrope (Christian Peoples Alliance) came last with about one per cent of the vote.

In the European elections, Theresa Villiers, who will fight the Chipping Barnet seat for the Tories at the next general election, kept her seat in Brussels as the Conservative party reaped 26 per cent of the London vote. Another two Tories, John Bowis and Timothy Tannock were also elected.

The Labour party also returned three London MEPs to Brussels after securing 24 per cent of the vote - Claude Moraes, Mary Honeyball and Robert Evans.

The Liberal Democrats achieved 15 per cent of the vote, winning one European seat for Sarah Ludford.

UKIP came fourth in the capital, just behind the Lib Dems with 12 per cent of the vote, with Gerard Batten being elected.

The Green party polled eight per cent, which means Jean Lambert retains her seat.

Other parties, including the British National Party and the Christian Peoples Alliance, scored 12 per cent.