POLICE have lifted security restrictions at the Conservative Party conference in Birmingham after a "potential security threat". 

Attendees were locked in the International Conference Centre (ICC), where the event is being held, for around an hour.

No one was allowed in or out of the building while police investigated the unspecified threat. 

Michael Fabricant was among those locked behind the security gate and said journalists and activists had the experience soundtracked by the pro-EU protestor Steve Bray playing the Benny Hill theme tune. 

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Bray is known for his long-running protest outside parliament and recently interrupted MPs while being interviewed live outside the building by playing Yakety Sax while Boris Johnson's government collapsed. 

All events inside the building, including Chancellor Kwasi Kwarteng's speech went ahead as planned as crowds began to build outside the building

Most high profile party figures, including the Prime Minster were present during the incident.  

The nature of the "potential security threat" is not known and the local force has been approached for further details. 

Birmingham Police tweeted: "Security restrictions at the ICC have been lifted following a potential security alert.

"Delegates and visitors are now able to leave the centre. We would like to thank everyone for their patience."