A goldfish was cooked alive in a frying pan and another was flattened and burnt with an iron.

A third fish was thrown against a wall and killed.

Burglars ransacked a house in Brighton, trashing all the rooms before torturing the pet fish.

The owners, a couple and their two teenage boys, were on holiday at the time.

A friend calling in to feed the pets was physically sick after discovering the mayhem.

He spotted the family's hamster was missing from its cage and feared it too had been killed but it was later found hiding under a sofa.

Police officers said they had never come across such a shocking case.

The offenders, believed to have been drinking, broke into the house by forcing a window.

They wrecked every room, smashing ornaments, spreading ice cream and sauce over chairs and couches, throwing food on to walls and carpets and ripping up Pokemon cards the youngsters of the house had collected.

One of the offenders went to a bedroom and poured hair dye over his head. One defecated on the floor and others urinated.

The intruders then turned on the goldfish.

One fish was taken out of a bowl and tossed alive into a hot frying pan.

Police were sickened by the incident. One senior officer said: "It was shocking and beyond my experience."

Four teenagers, one 11, two 15 and the fourth 16, were arrested and released on bail pending further police inquiries.

The RSPCA may be brought in to carry out its own investigation.

A spokeswoman for the Horsham-based society said: "What happened was cruel and despicable.

"We hope Sussex Police prosecute those responsible to the fullest extent of the law."