ANIMAL welfare group PETA has offered a $5000 reward for information over the strangling of a sheep in Casino High School earlier this week.
PETA has also warned that people who kill animals are often using animals as "practice" victims and can go on to commit violent acts against their fellow humans.
In a statement it listed several notorious serial killers including Jeffrey Dahmer, the so-called Milwaukee Cannibal, and Australia's Ivan Milat, who all tortured and killed animals before turning to human victims.
Port Arthur mass murderer Martin Bryant was also referred for mental health support twice as a child for torturing and harassing animals.
Press Officer for PETA Australia Laura Weyman-Jones said the sheep strangling case was "horrifyingly unique" but animal cruelty cases were being reported all the time.
"We don't offer rewards in all cases... it depends on whether there is any good leads in the case," she said.
"In this case we've spoken to police and there are no leads at the moment, so we consider it useful to offer a reward.
"We're hoping it is an incentive and people who know something... will come forward."
PETA Australia campaign coordinator Claire Fryer said animal abusers were "cowards".
"We're appealing to anyone with information on the person or persons responsible for this cruel act to come forward so that the perpetrators can be put where they belong: in jail," Ms Fryer said.
According to PETA, a study by University of Sydney psychology lecturer and NSW Police consultant Dr John Clarke demonstrated more than 60% of convicted animal abuse offenders had also committed an assault - and 17% had committed sexual assault.
The study found cruelty to animals was a better predictor of sexual assault than convictions for homicide, arson, or firearms offences.
Only 1 per cent of cruelty-to-animals offenders had no other convictions.
Cruelty to animals in NSW carries a penalty of up to $22,000 or five years' imprisonment under the Crimes Act 1990 and the Prevention of Cruelty to Animals Act 1979.
Anyone with information about this case is encouraged to call the Casino police on 02 6662 0099.
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