A number of pigs are understood to have died after a large fire broke out at a farm.
“The fire is in an agricultural unit, where a number of pigs are known to have sadly have been involved,” the service added in its statement on Facebook.
There was still “significant smoke” in the area, some 13 miles south of Oxford, and residents were advised to close doors and windows.
It comes after farmers warned that up to 120,000 pigs could be culled as the abattoir labour shortage has led to a backlog of animals ready for slaughter.
The backlog means that farms are struggling to find space for the extra pigs – leaving them with no choice but to cull them in the face of overcrowding concerns.
Prime Minister Boris Johnson drew criticism from farmers after responding to their concerns by pointing out that the pigs were all destined to die anyway.