The man behind a vicious Australian Web site used to harass teenage girls has dared authorities to take action.

Melton Web site designer Andrew Pallant claims his site, which has more than 1,300 posts containing unsubstantiated and often vulgar allegations, is designed to protect freedom of speech.

The site, which has been operating for more than a year despite repeated complaints, invites people to vent their fury about everyone from ex-girlfriends, to teachers, police and police informants, the Herald Sun reports.

Many of the victims are teenage girls who have had their name, photo and phone numbers posted, accompanied by invitations to bombard them with abusive phone calls and text messages or ask them for sex.

Pallant boasts that the site, which has caused chaos in western Victoria, gets about 3,000 hits a month. But although police have received complaints from parents and victims, they are powerless to prosecute Pallant or to close the site down.

"Victoria Police do not have any authority to take any blanket action against this type of site regardless of the location of the server," said Inspector John Manley, head of Victoria Police's E-crime squad.

Cobden father of four Peter Murfitt, whose 16-year-old daughter has been abused on the site, said many teenagers had been defamed.

"I'm wild as a meat axe about it. It's got to be dealt with one way or another," Murfitt said.

"If the police can't deal with it, then it will be dealt with in another way, and nobody wants that. These clowns need to be stopped."

Another Cobden teenager, who asked not to be named, said she had been bombarded with hundreds of explicit text messages and was scared to leave her house after her contact details were posted.

Pallant admitted to the Herald Sun his site was often used for bullying.

"I provide a service where people can write whatever they want," he said.

"If that means that someone is bullying someone then yes, I do provide (an avenue for) cyber bullying."

He also challenged the police to step in if people were upset by entries about them.

"The police haven't contacted me," he said. "I am not responsible, the person who wrote that is responsible. I don't put the pen in someone's hand."

Manley said police were powerless to close the site down.

"The offense would be committed by the person posting the content not the person who administers the site," he said.

"The offences that could apply would be stalking and possibly criminal defamation - there is no offence of cyber bullying."

Psychologist Michael Carr-Greg said he was astonished police were unable to stop the site from operating.

"This is by far the worst site I've seen," he said.

"The Australian Communications and Media Authority should close it down."

- News.com.au and the Herald Sun have chosen not to identify the Web site.

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