A New Zealand man has landed himself in a real-life version of Burn After Reading, the Coen brothers' film about two fitness centre employees who get their hands on a disc containing the memoirs of a CIA agent, with comic - and deadly - consequences.

Chris Ogle inadvertently found 60 US military files, including names and telephone numbers for American soldiers after buying an MP3 player in a secondhand shop in Oklahoma, USA. He came across the data when he connected the $18 (£12) device to his computer - hardly the rock tunes, snapshots and video one might expect to find on a secondhand MP3 player.

The military data included US social security numbers and even which female troops were pregnant, TV One New Zealand reported.

Details of equipment deployed to bases in Afghanistan and a mission briefing were also found on some files, displaying names such as "Bagram", a US base in Afghanistan. Most of the files are dated from 2005, so are unlikely to compromise US security, experts said. However, when a TV One reporter called some of the phone numbers listed, he found some still active.

The US military suffered a similar security breach in 2006 when shopkeepers outside Bagram said they were selling USB sticks with military data that had been stolen by some of the 2,000 Afghans employed as cleaners, office staff and labourers at the base. The information on some memory drives contained the social security numbers of hundreds of soldiers, including four generals, and listed troops who had completed nuclear, chemical and biological warfare training.

Official data loss from laptops left in taxis and bars, discs and memory drives seems to be the downside to digital government. In a particularly egregious case in the UK, the personal records of 25 million individuals, including their dates of birth, addresses, bank accounts and national insurance numbers on discs went missing in the post.

As for Ogle, he told TV One News that he would hand the files to US officials if asked.

The more I look at it, the more I see and the less I think I should be looking, Ogle said, mindful perhaps of what happened to the hapless Brad Pitt character in Burn After Reading.