Three men have been arrested by police investigating an unofficial 'ride out' which brought chaos to the streets of Leeds on Halloween.
Dozens of riders on motorbikes and quad bikes gathered on Kirkstall Road, forcing police to close it amid concerns for public safety.
A large group of bikes also broke away from the main pack and tore through pedestrian areas and shopping arcades in the city centre.
The men - two aged 27 and one aged 23 - have been arrested during the last week on suspicion of conspiracy to cause a public nuisance.
Police today said the trio had been released on bail as they appealed for help in identifying more of those involved and revealed that a further two potential ride outs were stopped last month.
The force said proactive policing operations had been put in place to prevent events planned for Leeds on December 11 and New Year's Eve going ahead.
It involved visits to those identified as organisers to warn them about a county court injunction granted to Leeds City Council, which bans people from participating in or organising any anti-social driving of vehicles.
Roads policing units and other officers were also deployed to prevent any build-up of vehicles at key locations on those dates.
The powers were secured last month on the same day that police carried out a series of dawn raids linked to the Halloween event.
The raids led to the arrest of six men and a woman on suspicion of conspiracy to cause a public nuisance.
Two other men, aged 28 and 29, were arrested days later after handing themselves in.
All nine remain on police bail as does the organiser, a 26-year-old man, who was arrested the day after the incident.
But officers are continuing to appeal for information to identify seven suspects shown on CCTV and other footage from the night.
Chief Superintendent Paul Money, Leeds District Commander, said: "We are continuing to take firm action to address the dangerous and anti-social behaviour that we saw on Halloween, which put people’s safety at risk and caused unnecessary fear to the public.
"We have now shown how proactive policing arrangements supported by the recently-granted injunction can have a strong deterrent effect on those planning similar events. We will be continuing to take a robust approach and I would like to remind people that we will not hesitate to make full use of the order to target any further planned events. With the likelihood of being arrested and having your vehicle seized, I think it would be very unwise for anyone to involve themselves in planning or taking part in any further ‘ride out’ events."
Anyone who knows the identity of the suspects shown in the images or who has any information is asked to contact officers on Operation Dice via 101, quoting crime number 13160541790.
Information can also be passed on to independent charity Crimestoppers anonymously on 0800 555 111.