Three Dutchmen were killed when their small aircraft crashed in a mountainous area, in northwestern Croatia, as it became known from the Dutch Ministry of Foreign Affairs.

The accident occurred at noon on Saturdayy, in a forest near the town of Ogulin, according to Croatian authorities. The Dutch airliner disappeared from radar while en route from Maribor, Slovenia to Pula, on the Adriatic coast.

Croatian Civil Aviation chief of investigators Danko Petrin told reporters that all three people on board were killed. The wreckage was found half destroyed by fire. “We will need to do DNA analyzes because the crash site is such that we could not visually determine the exact number of occupants,” he explained. However, according to the flight documents, the aircraft was carrying pilot and two passengers.

Dutch Foreign Ministry spokeswoman Felicia Bakker said all the victims were Dutch citizens.

The causes of the accident have not been clarified at this time.

The area where the plane crashed is inaccessible and possibly remains so to this day