The protest was organised and attended by Mr Gibney's brother

The images of Mark Gibney, 40, were shown by North Wales Police chief constable Richard Brunstrom at a closed road safety briefing for journalists.

The force has apologised to the family and the Independent Police Complaints Commission is investigating the case.

Mr Gibney's family, from Merseyside, organised the Llandudno demonstration.

North Wales Police chief inspector Gary Ashton said: "The event appears to have passed off safely.

"We're fully aware of the nature of the protest. An IPCC investigation is still ongoing so we have no further comment to make at this time."

Police admitted permission to show the photos had not been sought

Motorcyclists gathered on the promenade on Saturday morning, for what they say would be a peaceful protest.

Some riders came from as far afield as Bournemouth and Fife in Scotland.

Mr Gibney's 42-year-old brother Paul, who is among those organising the event, is also a biker.

Last month, Mr Gibney's family met with the Independent Police Complaints Commission (IPCC) which is reviewing the case following a voluntary referral from the North Wales Police Authority.

At the time, the family's solicitor Paul Beck said the meeting had gone well and had been a chance for the relatives to express their feelings about the case.

Mr Gibney's father William, 64, said: "The family's heartbroken...I took it at the time but it took a long time to get over it and then this has made it, it's like 50 times worse than the original when it happened."

He said the ride was important as it was the family's only way of protesting.

Motorcyclists were also outraged at the photographs being shown

"I think it will help a little bit of the hurt," he added.

Mr Gibney died in 2003 when his bike crashed on a bend on the B5105 between Cerrigydrudion and Ruthin in Denbighshire.

An image of his severed head lying on a grass verge was shown to journalists and council officials during a private road safety presentation by Mr Brunstrom on 26 April.

His headless torso was also shown as well as photographs of the bodies of two young men killed in a separate crash.

Afterwards, Mr Brunstrom claimed the pictures had been shown in confidence and accused some sections of the media of "distorting" the meeting.

Mr Brunstrom said the images were shown in confidence

He also defended his actions saying he had shown the images to "give the context" of his anti-speeding campaign.

The force apologised to the family "for the distress caused by the publicity" but this was rejected by the relatives who announced they were taking legal advice.

They want the chief constable to quit or be sacked.

The decision to show the photographs has also attracted criticism from several politicians including Welsh Secretary Peter Hain who described it as: "completely unacceptable".