Anti-fascist protesters broke into the BBC's west London headquarters on Thursday ahead of a white-supremacist party leader's appearance on a leading political debate show.

Hundreds of protesters gathered outside the BBC Television Center in an increasingly rowdy rally against British National Party chief Nick Griffin, who is due to appear on the broadcaster's "Question Time" program. At one point about 25 people breached a police cordon and ran into the center's lobby.

BBC footage showed some being pulled across the floor by their arms and legs by security.

SLIDESHOW: Protesters Invade BBC

The BBC said later that Griffin had managed to make it into the building, where he is scheduled to be a panelist on "Question Time" — a first for the far-right party.

Many politicians have condemned the invitation to Griffin, but the BBC says that as a publicly funded broadcaster it must cover all political parties that have a national presence. Justice Secretary Jack Straw, a senior member of the governing Labour Party Cabinet, is due to appear alongside Griffin.

The whites-only BNP opposes immigration and claims to fight for "indigenous" Britons. Griffin has a conviction for racial hatred and has denied the Holocaust in the past.

The party has tried to shed its thuggish image and enter the political mainstream. Earlier this year it won two European Union parliament seats, gaining 6 percent of British votes in European polls. It has no seats in the British Parliament.

The invitation to appear in front of several million TV viewers has divided Britain, but delighted the BNP, which is counting down the seconds until the broadcast on its Web site.

It has sparked a debate between free-speech advocates and those who say giving Griffin a platform lends legitimacy to unacceptable views and could provoke racist violence.

Several dozen demonstrators handed leaflets to staff outside BBC Television Center Thursday. Campaigners said they expected hundreds more to show up later when the show was being recorded.

Griffin said he expected a hostile reception, but had a right to be heard, and insisted his views had been misrepresented.

"If these people would only let us say what we want to say and then argue with what we've actually got to say instead of creating monsters and then being wound up about the monsters, everyone would get on far better," Griffin said.

The head of the Muslim Council of Britain, Muhammad Abdul Bari, said "allowing the BNP to air its toxic views will increase Islamophobia and give the BNP aura of respectability needed to spread their message of hate."

Prime Minister Gordon Brown said Griffin's appearance would expose the party's "racist and bigoted" views.

The BBC is wary of government interference in its political coverage. In the 1980s, the Conservative government banned radio and TV appearances by members of the IRA-linked Sinn Fein party. The broadcaster hired actors to read their words instead.

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