Kees Jan Dellebeke
In 1975 four Syrians intended to hijack an international train with Russian Jews in Amersfoort, the Netherlands, but following a tip-off by the Binnenlandse Veiligheidsdienst (BVD Dutch Security Service) they were arrested by the Amsterdam police on 5 September of that year.
The Syrians had been lifted off their beds in Hotel Neutraal at the Damrak in Amsterdam. When the police raided their rooms, pistols, submachine guns and a fake bomb, with wires and a battery, were found. A terror attack by four armed freedom fighter of the Syrian ´al Saiqa´ resistance movement had been prevented.
With the aid of SIGINT ( signals intelligence) foreign intelligence services had intercepted ( parts) of telephone numbers in the Middle East and shared these metadata with the BVD. .Every day long lists were manually compared by the BVD with data of international telephone conversations from the Netherlands. In 1975 calls were not yet effected automatically, but with the aid of a telephone operator.