Federal prosecutors on Thursday charged a 29-year-old man in the western city of Cologne with producing a biological weapon after police found highly toxic ricin in his apartment.
The Tunisian national has been in police custody since late Tuesday after special police and fire units found the ricin during a raid of his home.
Possession of the highly toxic substance is restricted by a 1997 international convention on chemical weapons. Exposure causes organ failure and death can occur within 36 to 48 hours, according to Germany's Robert Koch Institute, which categorizes ricin as a "potential biological weapon."
The suspect was suspected of violating the War Weapons Control Act and authorities are investigating whether he was preparing a "serious act of violent subversion."
Reported IS sympathies
The man first came to Germany in November 2016, local daily Kölner Stadt-Anzeiger reported. He reportedly had sympathies for the "Islamic State" (IS), the Islamist terror group that has carried out attacks in Europe and fought in the war in Syria.
Special units wore protective suits during the raid on the suspect's apartment
But prosecutors said they have not found evidence the man was planning an attack or that he was a member of any terrorist organization.
The newspaper also reported that authorities had been observing the suspect for some time. Police reportedly decided to raid his home after discovering that he had ordered ricinus seeds online.
German news agency dpa reported that the suspect's wife, who was also in the apartment on Tuesday, is not suspected of any involvement in the man's alleged plans.
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Editor's note: Deutsche Welle follows the German press code, which stresses the importance of protecting the privacy of suspected criminals or victims and obliges us to refrain from revealing full names in such cases.