BNP leader Nick Griffin says his party has claimed a "great victory"
BNP leader Nick Griffin has been elected to the European Parliament as the party won its first two seats.
Mr Griffin was elected for the North West region while Andrew Brons picked up another BNP seat in Yorkshire and Humber, where it won 10% of the vote.
Mr Griffin said the BNP was not racist, but won votes because it "spoke openly about the problem of immigration."
Labour's Harriet Harman described the result as "terrible" while Tory leader David Cameron said he was "sickened".
Mr Griffin was elected to Brussels even though the BNP polled fewer votes in the region than it had in 2004 - the slump in Labour support meant its share of the vote increased.
It meant that although the BNP came fifth in the popular vote in the region, it won a seat through the system of proportional representation used in the European elections.
The Labour Party, the Lib Dems and the Tories, by leaving the door to Britain open, has forced people to turn to a party which speaks openly about the problem of immigration
Nick Griffin BNP leader
Mr Griffin denied the party was racist, telling the BBC's Radio 4 Today programme: "There's a huge amount of racism in this country, overwhelmingly it is directed towards the indigenous British majority, which is one reason we've done so well in these elections."
He said the "ruling elite" had made the "indigenous majority ... second-class citizens in every possible sphere".
"The Labour Party, the Lib Dems and the Tories, by leaving the door to Britain open, has forced people to turn to a party which speaks openly about the problem of immigration and says that while there might be a few good things about it there's also a lot of bad things."
Ms Harman said: "I think it's a terrible thing that we've now got representing Britain in the European Parliament a party that is a racist party, a party that doesn't believe black people should even be allowed to join this party.
She added: "The British National Party have played on people's fears ...and we'll have to work to tackle the fear that lead to people to vote BNP."
Communities Secretary John Denham said that although "an element" of those who voted for the BNP would have been racists, most would have cast their ballots for the party because they felt ignored and excluded.
It sickens me as it should sicken everybody here that the British National Party has succeeded in these European elections
He told BBC Radio 4's The World At One: "We've got to make it very clear that we want to hear what those voters are saying."
Conservative leader David Cameron told party supporters: "It sickens me as it should sicken everybody here that the British National Party has succeeded in these European elections."
"It brings shame on us that these fascist, racist thugs have been elected to the European Parliament."
And Liberal Democrat leader Nick Clegg said politicians had to be "uncompromising" about the BNP which he said was "a party of thugs, of fascists".
But he added: "We should not dismiss the reasons why people have voted for the BNP - the anger, the frustration, the sense of alienation, the sense of powerlessness.
"We must listen to that and must react to that, that much is obvious."
The BNP won more than 120,139 votes in the Yorkshire region, slightly less than in 2004, but enough to take one of the six seats on offer in the region.
Nick Griffin is now an MEP even though he won fewer votes than he did five years ago
Successful candidate Andrew Brons acknowledged that his victory would not be "universally popular".
He said the party, which denies stirring racial hatred, had survived an "onslaught" by the media and the political classes during the campaign.
"Despite the headlines, money and misrepresentation, we have managed to win through," he said.
The election was the "first step" towards the UK removing itself from the "EU dictatorship", he added.
Dagenham Labour MP Jon Cruddas said the BNP "have not really moved on" in terms of its share of the vote since 2004 but the party had benefited from the drop in Labour support.
He added: "There's a long-term legacy here of us failing to bring people with us and deal with some of the issues that concern them, be they around housing, or about employment insecurity or the recession or immigration."
The BNP targeted the North West during the campaign, having had earlier success in local council elections.
It won one of its three English county council seats in Burnley in Thursday's elections.
As Mr Griffin arrived at the North West count - held in Manchester's town hall - on Sunday, his car was surrounded by noisy protesters, who broke one of its windows.
Mr Griffin returned later and entered the building by the back entrance, accompanied by several minders. Police said one man was arrested in scuffles when Mr Griffin tried to get into the building.
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