Police are investigating a fatal helicopter crash in Cairns, Australia, where a pilot was killed after the aircraft struck a luxury hotel and burst into flames during an “unauthorized flight.”

The crash occurred early Monday at the DoubleTree by Hilton Hotel, prompting the evacuation of hundreds of guests and staff.

Two holidaymakers on the top floor suffered minor injuries.

Authorities are still trying to identify the pilot and have not ruled out any possibilities, including whether the helicopter was stolen or if the crash was intentional, CNN has reported.

Charter company Nautilus Aviation confirmed the aircraft was used without authorization and is cooperating with the investigation.

Written by B.C. Begley