Police are investigating a series of abusive comments posted on the Twitter about musicians competing in a brass band competition.
The comments, posted on the social network during the Butlin's Mineworkers Open National Brass Band Festival in Skegness last weekend, compared one of the entrants to Adolf Hitler.
Other comments included likening the competition to the Auschwitz concentration camp and referring to other musicians taking part as "serial rapists" or paedophiles.
The offenders also posted pictures of competitors on to Twitter.
Iwan Fox, of online brass band magazine 4barsrest.com, was at the event and said he believed three or four people, all members of brass bands and two from two very prestigious bands, were behind the comments.
Mr Fox said the offenders were visitors to the contest and not involved in the event.
More than 4,000 people were involved in the event last weekend, with just under 100 brass bands from across the country taking part.
Mr Fox said: "It's highly competetive but it's always been quite friendly. It's all very family-orientated. But this was spiteful and nasty with racist, homophobic, comments made against individuals and references to the Auschwitz concentration camp.
"I think the people responsible started it off as a joke and then it got out of hand and I don't they realised the comments could be traced back to them."
He alerted the organisers of the event, Butlins, about the comments after they started to copy the 4barsrest.com icon on their Twitter feed and became more abusive.
"We cover the event with a rolling blog on our website and on Twitter where we have 5,000 followers. We suddenly noticed these tweets where they had tried to clone our logo."
The offending account has since been deleted.
A spokesperson for Lincolnshire Police said the comments had been brought to their attention but that no formal complaints had been made.
Meanwhile a Butlins spokeswoman said they were sure those responsible for the tweets had been dealt with.