Protesters from Animal Rising - the group that interrupted the Grand National at Aintree on Saturday - claim they were injured by officers from Merseyside Police.
More than 100 people were arrested and the steeplechase was delayed after activists attempted to scale fences around Aintree Racecourse, with some accessing the track and trying to glue themselves to fences.
In a social media video, a number of group members report officers being heavy-handed, with one in a sling saying he was 'poleaxed'.
One man who was arrested claimed there was a 'general lack of care' from the police and others reported being pepper sprayed, 'choked unconscious' and 'slammed' to the floor.
A spokesperson for Merseyside Police said: “The footage shown live on television on Saturday 15 April demonstrated the professionalism of our officers as they dealt with a co-ordinated protest involving large groups of people attempting to encroach onto the racecourse at Aintree.
“Despite the whole site covering an extensive perimeter of around 5km our officers, with the assistance of security staff and members of the public, were able to deal with the challenging situation in a safe and appropriate manner.
“Merseyside Police is aware of a video posted online showing a number of protesters making claims following their arrests on Saturday. As of today (Wednesday 19 April), Merseyside Police’s Professional Standards Department has not received a complaint in relation to any of these claims.
“If we do receive any complaints in relation to this matter, they will be reviewed thoroughly in accordance with the Police (Complaints) Regulations 2020.
“We respect the right to a peaceful protest and expression of views, but criminal behaviour and disorder will not be tolerated and sadly this is what took place at the Grand National on Saturday in an attempt to disrupt the race, which resulted in the arrests.”
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