A special service held today to mark the 200th anniversary of the abolition of the Slave Trade Act was interrupted by a protester.

The lone protester spoke to police outside the abbey. Toyin Agbetu ran from the congregation to a space in front of the altar shouting "you should be ashamed" and "this is an insult to us", bringing proceedings to a halt.

He was also heard to shout: "We should not be here, this is an insult to us. I want all the Christians who are Africans to walk out."

The Queen and Tony Blair were among those attending the commemoration in Westminster Abbey and were seated around 10ft from the disturbance.

Abbey staff attempted to control Mr Agbetu, who had a ticket for the event, with reports claiming up to seven bodyguards and two ushers surrounded him at one point.

Once outside, Mr Agbetu demanded that the Queen apologise for her ancestors' role in supporting the slave trade.

"The Queen has to say sorry," he said. "Elizabeth I commanded John Hawkins to take his ship.

"The monarch and the Government and the church are all in there patting themselves on the back."

Mr Agbetu claimed he was from the Ligali Organisation, an African Human Rights Organisation, and said he planned the protest in advance.

He added: "This nation has never apologised, there was no mention of the African freedom fighters.

"This is just a memorial of William Wilberforce."

Mr Agbetu was handcuffed after being taken into Dean's Yard. A police officer at the scene said he was arrested and later taken to Charing Cross police station.

Henry Bonsu was one of several people who ran up to Mr Agbetu as security guards tried to apprehend him.

Mr Bonsu, a radio presenter who knows Mr Agbetu but was not sitting with him, said: "It just happened at a moment of great solemnity. He just couldn't take it any longer.

"In the cold light of day, people will see he wasn't threatening the Queen. He wasn't threatening the Prime Minister. He just wanted to make his point when the cameras of the world were on the Abbey.

Mr Bonsu added: "The Queen, as ever, was unruffled but she looked interested."

David Burden, Receiver General of the Abbey Major General, said: "We deeply regret the incident but the service is continuing conducted by the Dean in the normal way.

"We are sorry that this incident has taken publicity away from the main service."

He defended the Abbey's security and insisted the Queen had been safe.

After the service, the Queen emerged from the Abbey to place flowers on the memorial to innocent victims outside before being driven away.

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