There is no dark mystery behind the hardcore pornography sent to former deputy president Jacob Zuma by the State as part of the preparation for his upcoming fraud and corruption trial, says the National Prosecuting Authority.

NPA spokesman Makhosini Nkosi said yesterday that the pornography was contained in hard drives seized by the Scorpions in raids on various premises in 2001.

When lawyers for Zuma and his co-accused, French arms company Thint, asked for relevant documentation and material for the trial, the prosecution team sent copies of all they had relating to the case without screening or editing it, said Nkosi.

"The prosecution team was obliged to do so, and in order not to prejudice the defence, had sent them everything," said Nkosi.

Nkosi said it was possible for the NPA to identify the premises the hard drive was seized from, but the authority "did not feel the need to do so" because the pornography was irrelevant to the case.

In papers filed at the Pietermaritzburg High Court this week, Zuma said his lawyers had "not yet fathomed" the relevance of the pornography.

He said the pornography was found on a computer hard drive, in a virus-riddled format, handed over by the State.

More than 15 images of copulating men and women were reportedly found on the hard drive, but the NPA would have been exposed to the same material that had apparently traumatised lawyers for Zuma and Thint.

Zuma's lawyer, Michael Hulley, described his unease about being sent the pornographic files. "I didn't even know sites like that were available on the internet," he was quoted as saying.

Nkosi said the pornography should be regarded as irrelevant, but the hard drive had been seized as part of the State's investigation.

"The defence can choose to shut down the porn. We gave them what we had, and if they got porn and viruses, so did we," said Nkosi.

He said the NPA had encountered a virus in one of the hard drives seized in the raids.

With acknowledgement to Glinnis Underhill and Cape Argus.