Two horses and a pregnant dog died in a fire at a compound which police say is being treated as suspicious.
Emergency services were called to the burning stable at Bridge Place, Eldon Lane, near Bishop Auckland, County Durham, on Sunday night.
The horse, foal and pregnant dog were trapped inside the stable building.
A Durham Police spokesman said police and fire investigators are carrying out inquiries at the scene to try and establish the exact cause of the fire.
The animals killed were a seven-year-old cob, an eight-month-old foal and a greyhound, which had been due to give birth in two weeks. They were valued at about £2,000.
They were in a stable which was inside a metal-sheeted compound.
Police hope to speak to witnesses who may have seen anyone acting suspiciously in the area.