Animal rights activists have been “sprayed with manure” as hordes of angry farmers confront them over a protest at Britain’s largest beef industry event, the campaign group has claimed.

The demonstration, which began in the early hours of Saturday, is said to have seen one protester taken to hospital after chaos unfolded outside Darlington Farmers Auction Mart (DFAM) in Co Durham.

Photos showed mask-clad activists from the Animal Justice Project (AJP) standing on the roof of the building holding banners and spraying coloured smoke flares.

A spokesperson for the group said campaigners have now been left “covered in excrement” after one event attendee allegedly used a sprayer to blast manure at them.

Another activist was injured after farmers allegedly ploughed towards a group of protesters in a JCB digger and “assaulted” them, the AJP claims.

The National Beef Association (NBA), which is organising the expo taking place over the course of this weekend, describes it as a celebration of the best of British beef, drawing in at least 5,000 guests  annually.

The AJP has said their protest was “peaceful” and “silent” and aimed to highlight “farmed animal suffering and environmental safety concerns”.

Police have been on the scene since 5am working to bring the demonstration to an end as guests and demonstrators clashed with one another but activists have said they intend to stay indefinitely.

Mark Dent, chair of DFAM, said earlier he believed the protesters were the sources of “intimidation”.

He told the PA news agency: “We respect people’s right to protest, but the way they go about it doesn’t help their cause.

“There is no respect for people’s property or livelihood. I’m afraid then you lose your moral high ground… It’s a tin roof and they’re jumping up and down on it, and it’s bending.

“They’ve got their faces covered. It’s intimidation (and) threatening behaviour. I’m all for people protesting what they believe in, but it’s the way they go about it – the face coverings, the intimidation.”

Animal Justice Project protest
The Animal Justice Project said farming glorifies the killing of animals (Animal Justice Project/PA)

He added: “If you have a pair of eyes you will see how important agriculture is around the world at the moment. Food is top of the agenda.”

An AJP spokesperson told PA: “We’ve been sprayed with cow poo by one farmer using a machine.

“It has been a peaceful protest and a silent protest and we are overwhelmed and outnumbered by hundreds of angry farmers.”

They added: “It’s really violent and there was one farmer who went along and sprayed everyone’s clothes. Shouting, swearing, spraying us with manure, ripped the banners down. It’s absurd.”

The group has said the farming event “glorifies the exploitation and killing of animals” which is “fundamentally wrong and unjust”.

Neil Shand, chief executive of the NBA, said: “Nobody has been hit by a tractor.”

A spokesperson for the NBA claimed there was a “wonderful atmosphere” at the event and did not comment further on the protest.

Durham Police said: “Our officers are working to bring the protest to a safe end and to minimize the impact on the wider community.”