Fourteen people have been arrested after dogs were stolen from a research centre.
Cambridgeshire Police said officers were called to MBR Acres in Wyton, near Huntingdon, just before 6am on Tuesday to reports of a break-in and "a group of protesters at the front gates".
Three people were arrested on suspicion of burglary and nine people were arrested on suspicion of aggravated trespass in connection with the protest.
A further two people were arrested on suspicion of burglary.
Protest group Animal Rebellion said in a statement that some of its supporters entered the facility at 5.30am and took 18 beagles.
Protests at the site hit the headlines in November 2021 after singer Will Young was involved in a demonstration.
Cambridgeshire Police said: "We were called at just before 6am to reports of a break-in at MBR Acres in Sawtry Way and the presence of a group of protesters at the front gates of the site.
"Three people were arrested on suspicion of burglary - a 29-year-old man from Sheffield, a 23-year-old man from York, and a 33-year-old woman, of no known address.
"Dogs were stolen from the site but there is no precise number at this time.
"Officers also arrested nine people on suspicion of aggravated trespass in connection with the protest.
"A further two people, a 20-year-old man of no known address and a 19-year-old man from Islington, London, were arrested at Stevenage Police Station on suspicion of burglary in connection with the incident.
"The incident at the site has now ended, however, a police presence remains.
"Police aim to ensure staff at the site can go about their lawful work, while protestors are able to express their views peacefully and safely, within the law."
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