Fourteen people have been arrested in connection with an incident at MBR Acres in Sawtry Way, Wyton, Cambridgeshire, on Tuesday (20 December).
Police were called at just before 6am to reports of a break-in at the site and a group of protestors at the front gates.
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.
They were a 23-year-old man from North London, a 28-year-old woman from Dalston, London, a 32-year-old man from Hackney, London, a 54-year-old man from Stalybridge, Greater Manchester, a 23-year-old woman of no known address, a 22-year-old man of no known address, a 30-year-old man from Worcester, a 20-year-old woman, of no known address, and a 20-year-old woman from Glasgow.
All the above are in custody at Thorpe Wood Police Station.
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.