Several anti-fascist protesters demonstrating against BNP leader Nick Griffin’s appearance on 'Question Time' broke through a police cordon outside BBC Television Centre today.
About 25 people managed to get past police lines during struggles with officers drafted in to protect the entrance to Television Centre in White City, west London.
Some appeared to have gained entry to the building where they were pursued by police.
The protesters, numbering about 500, were on an impromptu march down Wood Lane when the violence erupted.
Security guards had opened a gate to let a car into the front car park when about 30 protesters jumped over the barrier and ran towards the building.
About 50 officers were deployed to police the demonstration.
Scores of protesters converged on Television Centre ahead of the filming of the programme, which was due to be screened on BBC1 tonight.
A police helicopter circled overhead as officers guarded the front entrance.
Police sources said they had more than enough resources to deal with the crowd, which was expected to grow throughout the evening.
Audience members taking part in the programme were escorted in through the front entrance by police officers after showing their passports.
Mr Griffin, 50, was due to share the platform with Justice Secretary Jack Straw, Tory peer Baroness Warsi, Liberal Democrat home affairs spokesman Chris Huhne and writer Bonnie Greer.
As the debate approached, the chants outside Television Centre grew louder and louder with the crowd yelling: “We’re black, white, Asian and Jew, BBC shame on you”, and “we won’t let Nick Griffin through”.
The BBC said the disruption was dealt with promptly.
A spokesman for the corporation said: “A small number of people managed to get into Television Centre.
“However, they were identified and are being escorted from the building quickly.”