It was during Saturday morning that all journeys with DSB trains on Zealand were suddenly cancelled.

- We were contacted by our subcontractor who told us that their test environment had been compromised by criminal hackers, says DSB's head of security, Carsten Dam Sonderbo-Jacobsen, to DR.

Although it was not a direct attack on DSB, the subcontractor Supeo was forced to shut down its servers, preventing train drivers from running the trains for several hours.

- The attack was not directed at infrastructure or DSB, it was a financial crime, says DSB's head of security Carsten Dam Sønderbo-Jacobsen to Reuters.

The cyber attack is now being investigated, but it is unclear who or who are behind it.

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From floppy disks to the Coop crash - see examples of major hacker attacks over the years.

Photo: SVT