English National Ballet dancer Simone Clarke has made her first stage appearance since admitting being a member of the British National Party.
Simone Clarke has been principal dancer at the ENB since 2003
The dancer, who says she joined the far-right party in 2005, took the lead role in Giselle at the London Coliseum.
About 40 anti-racism campaigners held a protest outside the ballet, calling for Clarke to be sacked.
Two demonstrators also made it into the audience, shouting "no racism in the arts" from the stalls.
It failed to interrupt the performance, and the pair were met with cries of "shame" from the audience, before security guards bundled them out of the auditorium.
Protestors gathered outside the London Coliseum
The ENB said it would not comment on its dancers' political views "or any other aspect of their personal lives".
"Any personal view expressed by one of our employees should not be considered as endorsed by the company," it said in a statement.
Its response was dismissed by campaign group Unite Against Fascism, which organised today's demonstration.
"The ENB is a publicly funded organisation," said Savvy Dhalu from the group.
"We believe it is duty-bound to investigate whether her membership of the BNP contravenes the principles of the organisation which employs her.
"She should be suspended until this investigation is carried out."
Technical union Bectu, which represents many in the theatre industry, has also condemned the ballerina's membership of the BNP.
"She has brought our industry into disrepute," said assistant general secretary, Gerry Morrissey.
"Simone Clarke earns her living in the subsidised arts and with this goes certain responsibilities, with which she has failed to comply."
But the Liberal Democrats said Clarke should be allowed to keep her job because - although it did not agree with the party's views - the BNP was not an illegal organisation.
"It would set a deeply worrying precedent if employment with publicly funded organisations depends on whether or not a person's political views are palatable to the political and media establishment," said Lib Dem culture spokesman Richard Younger-Ross.
"We need to remember that this witch-hunt has provided the BNP with much more publicity than they would have otherwise received."
The Arts Council, which funds the ENB to the tune of £6m a year, requires recipients to be "aware of how their work contributes to race equality and promoting good race relations".
However, the organisation has confirmed it will not withdraw its grant to the ballet company.
Clarke has defended her views in an interview with the Mail on Sunday.
She told the newspaper she joined the BNP after reading its manifesto.
"I'm not too proud to say that a lot of it went over my head but some of the things they mentioned were the things I think about all the time, mainly mass immigration, crime and increased taxes," she said.
Although she advocated tighter border controls, the ballerina - whose partner is a Cuban immigrant with a Chinese father - said she was not in favour of "removing foreigners".
The interview only increased anger among her critics but barrister Jill Brown, an expert in employment law, said it was unlikely the dancer would lose her job over the revelations.
"Private political views are not grounds for dismissal normally in employment law," she told Five Live.
The BNP currently holds more than 50 council seats in the UK.
On its website, it portrays itself as the only party "prepared to defend our traditional principles against the politically correct agenda" of Tony Blair and David Cameron.
A BNP councillor from Barking and Dagenham, Richard Barnbrook, attended Clarke's comeback performance, saying he was "supporting her freedom of expression".