The army chopper was Dutch owned but crashed into the Netherlands territory in the sea according to officials. Among the four that were on board two have died. The other two onboard were found and not seriously harmed. It is still unclear to what caused the crash and the investigation remains open as military divers will work to retrieve the helicopters black box.
Source: https://www.thedefensepost.com/2020/07/20/dutch-army-helicopter-crash/
