Image copyright KVOA Image caption Mr Lotsof (left) defended his position over child pornography to KVOA reporter Zack Briggs

An online petition has been launched by residents of the town of Benson in the US state of Arizona against a radio station which broadcast advice late at night on how to hide child pornography.

Statements aired by the station over a two-year period gave tips on how to disguise viewing such images.

The petition accuses the station of broadcasting "a sickening message".

Cave 97.7 FM owner Paul Lotsof has publicly stated he disagrees with Arizona's laws on child pornography.

He told KVOA News 4 Tucson that he had performed a public service by broadcasting the advice, which recently has been taken off air.

Image copyright Cave 97.7 Image caption Cave 97.8 FM invites listeners on its website to submit public service announcements as long as they benefit a non-profit organisation

Mr Lotsof argues that possession of child pornography should not be a crime and that sentences for it are draconian.

"In many cases the penalties for pictures is worse than the penalty for murder," he can be heard saying on a clip posted on YouTube by critics of his "outrageous" views.

Mr Lotsof maintains there is a distinction between viewing paedophile images and committing paedophile acts.

"The difference is [that in] one case, you're molesting children and abusing them, causing children to do things that are not natural for children to do, and [in] the other case, they're just possessing pictures," he told News 4 Tucson.

Cave 97.7 describes itself as "south-east Arizona's most powerful radio station". Audience figures are not available on its website.

The petition on Change.org accuses Cave of broadcasting "a sickening message about a huge issue that plagues this country".

"There is no excuse for this and [the station] needs to be shut down," it states. "We can keep this garbage out of our community."

Image copyright Change.org Image caption The petition on Change.org accuses the radio station of "crossing a huge line"

The advice was broadcast under the format of a Public Service Announcement (PSA) - a way in which messages in the public interest are disseminated via the media.

Federal Communication Commission officials told News 4 Tucson that there were no rules which clearly articulated what could or could not be broadcast in relation to PSAs.

The US has a long tradition of upholding the principle of freedom of speech. But police in Benson say they are investigating whether the station's PSAs are in breach of the law, and that the children in pictures are victims of a crime.

"Freedom of speech does not include telling people to commit crimes and continuing to pass on this information could lead to judicial action being taken," a police statement said.

"We are now seeking legal advice on actions that can be taken for the content that has already been released and to ensure this kind of information is not released again."

Arizona has some of the toughest laws in the US on child abuse and exploitation. In 2003 a high school teacher was sentenced to 200 years in prison after he was caught with thousands of images of child abuse on his computer.