Watch a report by ITV News Anglia's Matthew Hudson.
The singer Will Young handcuffed himself to the gates of a puppy breeding centre as part of a long-running protest by campaigners.
He was pictured by the Twitter account Camp Beagle, which represents the demonstrators who camped outside the facility's gates for several months.
Protesters have been calling for the MBR Acres site near RAF Wyton, which breeds beagles for animal research, to be closed down.
They argue that modern computer research could be used instead of experimenting on animals.
Mr Young said he had been moved to travel to Huntingdon to join in after hearing of the protest.
"I'm an animal lover, and I just couldn't sit at home," he said. "I was unaware until about six months ago that even facilities like this existed."
He said he was prepared to be arrested for his actions.
"I got some handcuffs from Amazon - back in the day they would have been used for different things but I've had those experiences," he joked.
"I deliberately handcuffed myself to the gates... They are called the gates of hell," he added.
The singer and actor is known for his time on ITV show Pop Idol in 2002 when he became the first winner of the show.
The protests ramped up in the summer after footage emerged allegedly showing the kind of treatment experience at research laboratories.
The singer has now left the site.
Experiments are not carried out at the site, but protesters object to the fact that puppies are reared indoors - though MBR insists that the animals are healthy, content and comfortable.
A spokesman for MBR said it had an injunction from the High Court to prevent protesters carrying out unlawful activities near the site.
He added: "We have stressed throughout the protest that we have no interest in stifling legitimate protest provided it is conducted lawfully and peacefully. But we remain concerned that protestors continue to conduct unlawful activities at the sites as part of their campaign including unwarranted harassment and intimidation of our staff and others."
Protesters are barred from accessing a designated exclusion area in front of the gates to prevent harrassment of those entering, said the spokesman.
"Our business will continue to manage and run its operations in full compliance with Home Office regulations and with our normal high welfare standards. However, it is difficult to ignore where there is a peaceful protest a policing presence would not be needed, including a safe, clean environment that all local authorities are required to manage.
"We remain proud of what we do every day because our work allows the progress of medicine to save millions of human and animal lives.”