Children who posed naked for a controversial art exhibition will be interviewed today by police investigating whether a prominent photographer and Sydney art gallery breached child pornography laws.

Police last night raided the Roslyn Oxley9 Gallery in Paddington, in Sydney's eastern suburbs, just hours before the opening of the exhibition by photographer Bill Henson.

The exhibition shows photographs of naked children as young as 12 in a variety of poses — some of which may have been taken up to a decade ago. Henson has said none of the children featured is a professional model.

He has defended his work as seeking to explore "something which is absolutely inviolate and unknowable". He has told The Australian: "You can't control the way individuals respond to the work."

Political leaders and child safety campaigners have responded with anger. Prime Minister Kevin Rudd has said the images are "revolting" and have no artistic value.

"Kids deserve to have the innocence of their childhood protected," he has said. "Whatever the artistic view of the merits of that sort of stuff — frankly I don't think there are any — just allow kids to be kids."

Henson has been called one of the "leading contemporary artists" by the Art Gallery of NSW and the Roslyn Oxley9 gallery's manager Amanda Rowell has called him a "master." She has said the reaction to this exhibition has been blown out of proportion.

"It has never been like this before. This is no different to any other exhibition he's had and he's had many exhibitions here," she said. "He's a master, there's no one in the world like him."

But his use of pre-teen nudity has been written off as little more than a fetish for child porn. "He has a tendency to depict children naked and that is porn," said Hetty Johnston of child protection group Bravehearts.

NSW Premier Morris Iemma has said the images are "offensive and disgusting". "I don't understand why parents would agree to allow their kids to be photographed like this," he said.

Sydney's The Daily Telegraph understands that a squad of police spent several hours yesterday examining the photographs of boys and girls believed to be about 12 years of age. Detectives from the Child Exploitation Internet Unit were also called in to investigate the contents of the gallery's Web site.

The web page displayed all 41 of the naked images, but they have now been taken down and a spokesman from the Australian Communication and Media Authority said the web link was being investigated.

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