Six piglets died in a suspected arson attack on straw and hay in a field in Buckinghamshire.
Two fire crews were called to Bockmer Lane in the village of Medmenham, near Marlow, shortly before 1400 BST.
Ten tonnes of straw were alight and the fire had killed six piglets, the fire and rescue service said.
The fire was brought under control by 1536 BST and an investigation into the cause, believed to be arson, has begun. Crews remain on site damping down.