Horny Japanese navy crew who exchanged pornographic content on their PCs have sparked an embarrassing information leak emergency. Local media in Japan reported how sensitive data relating to the country's missile defence systems was copied accidentally along with the porn content.

The Daily Yomiuri says that Japanese police have launched an investigation after a naval officer took home a memory stick containing sensitive information about Japan's maritime Aegis Missile Defense System.

The officer admitted that he unwittingly copied the classified data onto his home computer while he was downloading the pornography.

Police suspect that the foul up was part of a prolific pornographic 'swap club' involving more senior officers, because the three men actually implicated in the scandal did not have access to the leaked information in the first place.

US concerns

The leak would be serious on its own, but the fact that the US also uses the Aegis Missile Defence System that it might have had serious implications on worldwide security.

Japan is particularly tetchy with regard to missile defence due to volatile relations with the long range missile-equipped radical nation of North Korea. As a result, Japanese defence spokespeople declined to comment on the matter.

This is an extreme example of a common problem that can happen within businesses when USB flash drives are reused and exchanged without being formatted in between.