A seven-month-old puppy was drowned in the bath during a burglary in Great Yarmouth in Norfolk.
Burglars broke into a house in Cobholm Close on Wednesday 5 April and stole a number of items including a computer.
It is believed Benji was drowned by the burglars.
Benji's owner Mark Phillips said the puppy was "part of the family from day one" and his death had left them "devastated".
Mr Phillips described Benji as a "friendly, lovable dog" who was "great with children" and always wanting to play.
It was Mr Phillips' brother-in-law, Gareth Deacon-Walker, who discovered the dead puppy.
Mr Deacon-Walker came round to the house after the burglary, and after searching for the dog he found him "floating in the bath. Dead."
Mr Deacon-Walker also described Benji as "family member", saying he was "more than a dog, he was one of us".
Detective Sergeant Richard Wallis said: "This is a particularly cruel crime.
"I would urge anyone who may have seen any suspicious behaviour in the area at around the time of the burglary to come forward."
- Anyone with information should contact Great Yarmouth CID on 101 or Crimestoppers anonymously on 0800 555111