A man is being prosecuted for allegedly publishing a story detailing the kidnap, torture, mutilation and murder of the pop group Girls Aloud.

Darryn Walker, 35, is due to appear before a judge accused of writing and posting the obscene blog on a fantasy porn website. His is seen as one of the most significant censorship cases since publisher Penguin was prosecuted for sanctioning D.H. Lawrence's novel Lady Chatterley's Lover in 1960.

The case is the first test of the 1959 Obscene Publications Act since pornographic material has become widely available on the internet, and is one of the first involving the written word in recent years. The Act, which has not been updated since it was conceived, made it illegal to publish material that tends to "deprave and corrupt" those reading or viewing it.

The blog article, understood to have run to 12 pages, was headlined "Girls (Scream) Aloud" and allegedly described in detail the rape and killing of the girl group. Although the website has a foreign host, prosecution is still possible because the alleged author was identifiable as a British citizen living in the UK.

The Internet Watch Foundation discovered the blog last year and informed the Crown Prosecution Service. In February, Mr Walker was arrested at his home in South Shields, near Newcastle, by officers from Scotland Yard's Obscene Publications Unit.

Mr Walker, a civil servant, was charged with the publication of an obscene article on 10 July, and has already appeared before South Tyneside Magistrates, where he entered no plea and was granted unconditional bail, a Crown Prosecution Service spokesman said. He is due to appear at Newcastle Crown Court later this month.

A Scotland Yard spokeswoman said it was unusual to see a prosecution brought under which did not involve pornographic images in magazines or DVDs. She said: "The vast majority of prosecutions brought under the Obscene Publications Act have related to images; be they photographs, computer-generated images or videos. It is very unusual to be prosecuted for a case involving the written word."

The most celebrated case of prosecution under the Act came just a year after it was made law. D.H. Lawrence's Lady Chatterley's Lover was accused of having a corrupting influence on all who read it. The publisher, Penguin Books, was found not guilty and, within a year, the erotic novel had sold more than two million copies.

Girls Aloud shot to fame in 2002 after appearing on reality music show Popstars: The Rivals on ITV. They have since become one of Britain's most successful pop groups, with a record-breaking 18 consecutive top 10 singles.

The group is made up of Nadine Coyle, Sarah Harding, Nicola Roberts, Kimberley Walsh and Cheryl Cole, who is now a judge on another ITV reality music show, The X Factor.