Ben Newman, a member of the activist group Animal Rising who ran on to the course at Epsom shortly after the start of the Derby, was sentenced to two months’ imprisonment, suspended for 18 months, for contempt of court on Wednesday after he admitted breaching an injunction granted to the Jockey Club in May to prevent disruption at the Derby meeting.

Newman, who also agreed to pay £10,000 towards the Jockey Club’s costs, climbed over a fence on the inside of the track near the furlong pole and ran towards the finishing line before being removed from the course by police and security staff. He subsequently pleaded guilty to causing a public nuisance and was sentenced to 18 weeks’ imprisonment, suspended for two years, ordered to complete 80 hours of unpaid work and also pay costs and surcharges totalling £1,356.

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Wednesday’s hearing before Mr Justice Miles at the Royal Courts of Justice in London was told that Newman admitted to both his knowledge of the injunction against incursions onto the track, and also that he and other members of the group Animal Rising still intended to try to stop the Classic going ahead, in a radio interview on 2 June.

However, it also heard that Newman had “reflected on his behaviour” while on remand for 36 days after his protest, and “expressed genuine remorse” for his actions and the distress caused to security staff and other individuals, who went on to the course on 3 June to remove him knowing that the Derby field had already set off. Newman stated that it had not been his intention to enter the track once the race was under way.

Passing sentence, the judge said that these mitigating factors had been taken into account. He also ordered that Newman should not attend any of the Jockey Club’s 15 racecourses until the 18-month suspension had expired, and confirmed that the original injunction remains in place ahead of next year’s Classics.

“We were always very clear that if anyone chose to breach the injunction, then we would not hesitate to take further action,” Nevin Truesdale, the Jockey Club’s chief executive, said after the hearing. “It has always been our intention for that action to be both clear and proportionate and we accept the sanction imposed on Mr Newman today.

“More widely, it is our sincere hope that by pursuing this matter in the high court, it sends a very clear message to anyone who might in future consider disrupting races in such a way, that we will never tolerate illegal and reckless behaviour of this kind.”