A man was arrested and drugs, thousands of pounds in cash and two dogs were seized after police raided a campsite near Waddesdon yesterday.
A 37-year-old man was arrested on suspicion of possession with intent to supply class A and class B drugs.
Police raided the site in Wotton Underwood early in the morning and found cannabis and a large amount of crystallised white powder believed to be mephadrone, also known as MCAT or meow meow.
Several thousands of pounds in cash was also seized under the Proceeds of Crime Act.
The dogs were seized after it was alleged the owner was believed to be under a court order banning him from having animals.
The man, who is from Wotton Underwood, has been released on bail until February 14.
Former Prime Minister Tony Blair owns the multi-million pound Grade I listed South Pavilion in the village.