Rijswijk assassination suspects linked to prior reconnaissance and hidden weapons

During an initial preparatory hearing, Dutch prosecutors revealed new details regarding the May 1, 2025, assassination of Cemil Önal in Rijswijk. Önal was shot multiple times in the head and upper body while sitting on a hotel terrace.

Prosecutors allege that co-defendant Hasan Y. and the suspected shooter conducted reconnaissance hours before the attack. Surveillance footage reportedly shows the two men in the vicinity of the hotel prior to the shooting, with Y. walking across the victim's terrace just fifteen minutes before the incident. Although Y. was not the shooter, the Public Prosecution Service (OM) contends he played an interchangeable role, noting that he discarded a firearm and clothing following the murder.

Investigations revealed that Y. had been detained in Barneveld on April 25, 2025, for driving a car with stolen license plates. While released at that time, police later discovered various firearms in a hidden compartment within that same vehicle in August 2025. Y. was apprehended in Germany and extradited to the Netherlands.

The suspected shooter, a 34-year-old man born in Turkey, is currently detained in France for weapons possession and is expected to be extradited to the Netherlands after October. A third suspect, a 48-year-old man from Bergheim, Germany, has been released pending a decision on prosecution.

Önal was himself a suspect in a 2022 double homicide in Northern Cyprus involving businessman Halil Falyali. He had recently been released in the Netherlands following an extradition request from Turkey.