Croatian media say that this is the worst railway accident to have occurred in independent Croatia to date, adding that if the train had derailed into a ravine 30 m ahead, the death toll could have been much higher.

The accident happened when the two-carriage tilting train of the RegioSwinger type carrying about 90 passengers derailed at 10:08 GMT (12:08 local time) in a remote area near the village of Rudine, around 30 km (19 mi) from its destination.

According to Croatian news reports, the cause of the derailment was slippery fire retardant that was just sprayed on a steep downhill section of the track, a normal practice in extreme summer heat but executed improperly[2] using a new chemical.

[4] On 27 July 2009 a cleaning operation on the 11 km (6.8 mi) stretch of railroad between the stations Kaštel Stari and Labin Dalmatinski begun, but was stopped within an hour because of a new discovery important for the investigation.

[8] Two people who played the most important role with purchase and application of the retardant were, by the order of new HŽ Infrastructure director, put on suspension and subsequently fired from the company.