Animals have been kicked and stamped to death in a spate of "absolutely horrific" attacks in Hartlepool.
Police are investigating after a number of allotments between Elmwood Road, Thornhill Gardens and Wiltshire Way were targeted over the last two days.
A goose, chickens and pigeons were killed, according to police, while others were let out to escape.
One of the victims was a 69-year-old man, whose shed was broken into, and a chicken coup was opened between 1pm on Sunday and 9am on Monday, say police.
A Cleveland Police spokesman said: "Three chickens were removed, but one was left on the floor and stamped to death.
"The suspect or suspects then also removed a 15-year-old goose from a hen house and stamped it to death, before burying its head in mud at the allotment."
A 57-year-old man's racing pigeons were removed from another allotment between Sunday and Monday, before the birds were stamped to death and left on the ground, police added.
Another victim was a 69-year-old male.
The police spokesman added: "A 69-year-old male victim also suffered a break in to his allotment where he keeps pigeons, however the suspect or suspects were unable to get to the birds.
"They did cause damage within the shed and damaged locks during the burglary.
"Neighbourhood officers are investigating these incidents and they are liaising with colleagues at Hartlepool Borough Council, which is the landlord for the allotments.
"Anyone with information on these incidents is asked to contact PC Jodi Prosser-Mallon via the non-emergency number 101.
"Information can also be passed anonymously to the independent charity Crimestoppers by phoning 0800 555 111 or via their website at www.crimestoppers-uk.org"