Mounted police were outside a screening of the hit Minecraft film in Lancaster after incidents including an assault on a teenage boy.
The teenager was taken to hospital with injuries after attending Vue Cinema on Church Street on Thursday.
He had gone to watch A Minecraft Movie, a film based on the popular video game Minecraft.
Police said there had been reports of "several incidents when individuals have left the cinema after watching Minecraft" and they included damage and assaults.
"We received a report of an assault on Anchor Lane, Lancaster, at around 1pm on April 10," said a spokesperson for Lancaster Police.
"It is reported that a teenage boy was assaulted following an altercation in the cinema.
"The teenager was taken to hospital with injuries and has since been discharged.
"Enquiries are ongoing, and anyone with information is asked to contact 101 quoting log 0591 of 10th."
Police horses Rosehill and Hutton were outside the cinema on Friday as part of a patrol to tackle anti-social behaviour.
"Luckily tonight they’ve helped keep things on track and are happy to report there were no issues," said a spokesperson for Lancashire Mounted Police.
"There have been reports this week of several incidents when individuals have left the cinema after watching Minecraft.
"These have included incidents of damage and assaults."
The spokesperson said the cinema "should be an enjoyable and safe environment for everyone".
Image: Lancashire Mounted Police
Incidents at screenings of A Minecraft Movie have been reported elsewhere at UK cinemas, as young viewers copy a trend popularised on TikTok.
Viral clips have shown large groups of youngsters jumping out of their seats, throwing popcorn and drinks, and screaming, during a scene in the film showing the arrival of the 'Chicken Jockey' character.
Cinemas across the country have been warning customers against disruptive behaviour during screenings of the movie.
Beyond Radio has contacted Vue Cinema. A spokesperson said they will not be making a comment.
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