Radu was, according to Ion Mihai Pacepa, a radiological weapon used against dissenters and critics by Nicolae Ceaușescu's Securitate.
The supposed weapon was intended to lead to cancer which would result in death within months after the exposure.
The Romanian "Service K", founded in 1950s by the Soviets using the KGB model, was tasked with creating excuses to eliminate political prisoners whom they considered dangerous to the regime's power.
The same Pacepa claimed the service was also in charge of discreetly murdering political prisoners and making it appear like a suicide or natural death.
[1] Historian Mihai Pelin claimed in a book on Radio Free Europe, Melița și Eterul, that there was no such weapon, but others, such as RFE journalist Nestor Ratesh, argue that Pelin also claimed the Securitate was not involved in the 1981 RFE bombing, a position that was allegedly contradicted by Romanian president Ion Iliescu.