Rotterdam police search Ringvaartplas for weapon used in 2014 murder

Dutch police have launched a search in the Ringvaartplas in Rotterdam-Prinsenland for a firearm potentially used in the 2014 murder of Rob Zweekhorst. The investigation, known as the Berkelse vergismoord, follows the shooting of the 44-year-old Zweekhorst in Berkel en Rodenrijs while he was walking his dogs.

The case is characterized by the suspicion that the shooter targeted a neighbor rather than Zweekhorst. While a suspect was apprehended in 2018, a 59-year-old man from Schiedam was acquitted by a court in June 2026 due to a lack of conclusive evidence.

Following a tip, specialists utilized scans to locate objects on the bottom of the Ringvaartplas and conducted manual searches in the water. Additionally, a man reported retrieving a weapon from the lake last year; authorities are currently investigating whether this object is relevant to the case. The National Underwater Investigation Team and the Seaport Police are continuing their efforts. A reward of 25,000 euros remains active for information leading to the arrest of the perpetrator.